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COPYRIGHT DEPOSIT. 



GAS AND FUEL ANALYSIS 
FOR ENGINEERS. 



A COMPEND FOR THOSE INTERESTED IN THE 
ECONOMICAL APPLICATION OF FUEL. 



PREPARED ESPECIALLY FOR THE USE OF STUDENTS 

at the 
MASSACHUSETTS INSTITUTE OF TECHNOLOGY. 



AUGUSTUS H. GILL, S.B.. Ph.D., 

Professor of Technical Analysis at the 

Massachusetts Institute of Technology, Cambridge, Mass. 

Author of ' 'A Short Handbook of Oil Analysis, ' ' 

" Engine Room Chemistry." 




NINTH REVISED EDITION 
TOTAL ISSUE, NINE THOUSAND 



NEW YORK 

JOHN WILEY & SONS, Inc. 

London: CHAPMAN & HALL, Limited: 

1920 





Gc 



Copyright, 1896, 1902, 1907, 1908, 1911. 1913. 1917. 1920, 

BY 

AUGUSTUS H. GILL. 



6/20 



n 



PRES3 OP 

BRAUNWORTH It CO- 
BOOK MANUFACTURER8 
BROOKLYN, N. Y. 



JUL 31 1920 

©CI.A570896 



*^\ 






PREFACE. 



THIS little book is an attempt to present in a con- 
cise yet clear form the methods of gas and fuel analy- 
sis involved in testing the efficiency of a boiler plant. 
Its substance was given originally, in the form of 
lectures and heliotyped notes, to the students in the 
courses of Chemical, Mechanical, and Electrical En- 
gineering, but in response to requests it has been 
deemed expedient to give it a wider circulation. 

At the time of its conception, nothing of the kind 
was known to exist in the English language ; in 
German we now have the excellent little book of Dr. 
Ferdinand Fischer, " Taschenbuch fur Feuerungs- 
Techniker." 

The present book is the result of six years' experi- 
ence in the instruction of classes of about one hun- 
dred students. It is in no sense a copy of any other 
work, nor is it a mere compilation. The author has 
in every case endeavored to give credit where any- 
thing has been taken from outside sources; it is, how- 



IV PREFA CE. 

ever, difficult to credit single ideas, and if he has 
been remiss in this respect it has been unintentional. 

The study of flue-gas analysis enables the engineer 
to investigate the various sources of loss ; and if this 
compend stimulates and renders easy such investiga- 
tion, the writer's purpose will have been accomplished. 
The necessary apparatus can be obtained from the 
leading dealers in New York City. 

The author wishes to acknowledge his indebtedness 
to our former Professor of Analytical Chemistry, Dr. 
Thomas M. Drown, and to Mrs. Ellen H. Richards, 
by whose efforts the department of Gas Analysis was 
established. 

He will also be grateful for any suggestions or cor- 
rections from the profession. 

Massachusetts Institute of Technology, 
Boston, November, 1896. 



PREFACE TO THE NINTH EDITION. 

The changes in the present edition include the fol- 
lowing: General revision and addition of numerous 
explanatory notes and references; the calculation of 
losses in chimney gases by the molar or volumetric 
method and the rewriting of the chapter on pyrometry. 

Massachusetts Institute of Technology, 
Cambridge, March, 1920. 



CONTENTS. 



CHAPTER I. 

PA«B 

Introduction. Sampling — Sampling-tubes. Suction Appa- 
ratus. Gas-holders i 



CHAPTER II. 

Apparatus for the Analysis or Chimney-gases. Apparatus of 

Orsat, Bunte, and Elliott 12 

CHAPTER III. 

The Measurement of Temperature. Thermometers — Le 

Chatelier Pyrometer — Metals and Salts 28 

CHAPTER IV. 

Calculations. "Pounds of Air per Pound- of Coal," and Per- 
centage of Heat Carried off by the Flue-gases. Loss due to 
Formation of Carbonic Oxide. Loss due to Unconsumed 
Fuel 32 

CHAPTER V. 

Apparatus for the Analysis of Fuel and Illuminating Gases. 

Apparatus of Hempel 48 

CHAPTER VI. 

Preparation of Reagents and Arrangement of the Labora- 
tory 63 

V 



VI CONTENTS. 

CHAPTER VII. 

PAGE 

Fuels, Solid, Liquid, and Gaseous: their Derivation and 
Composition 70 

CHAPTER VIII. 

Fuels. Methods of Analysis and Determination of the 
Heating Value. Determination of the Various Constituents. 
The Emerson Bomb and Junkers' Gas-calorimeter 84 

APPENDIX. 

Tables 127 

Coal and Fuel Oil Specifications 133 






LIST OF ILLUSTRATIONS. 



Fig. page 

i. Gas Sampling-tube 3 

2. Sampling Apparatus 4 

3. Sampling Apparatus for Mine-gases 6 

4. Gas-tube 6 

5. Richard's Jet-pump 8 

6. Bunsen's Pump 8 

7. Steam Air-pump 9 

8. Orsat Gas Apparatus 13 

9. Bunte Gas Apparatus 19 

10. Elliott Gas Apparatus 23 

11. Melting-point Boxes 31 

12. Bunte's Flue Gas Chart , Between pages 40 and 41 

13. Bunte's Flue Gas Chart Enlarged , 42 

14. Azbe's Combustion Chart 44 

15. Kreisinger and Ovitz's Chart of Losses 46 

16. Hempel Gas Apparatus 49 

1 7. Hempel Gas Apparatus 50 

18. Muencke's Aspirator 68 

19. Marks' Chart for Carbon in Coal 87 

20. Combustion-furnace 88 

21. Emerson Bomb 97 

22. Emerson Bomb and Calorimeter 99 

23. Maujer's Chart 115 

24. Junker's Gas-calorimeter, Section 117 

25. Junker's Gas-calorimeter 118 

vii 



GAS AND FUEL ANALYSIS. 



CHAPTER I. 
INTRODUCTION AND METHODS OF SAMPLING. 

UNTIL within recent years, the mechanical engineer 
in testing a boiler plant has been compelled to con- 
tent himself with the bare statement of its efficiency, 
little or no idea being obtained as to the apportion- 
ment of the losses. Knowing the composition and 
temperature of the chimney-gases and the analysis of 
the coal and ash, the loss due to the formation of car- 
bonic oxide, to the imperfect combustion of the coal, 
to the high temperature of the escaping gases, can 
each be determined and thus a basis for their reduc- 
tion to a minimum established. 

By the simple analysis of the chimney-gases and 
determination of their temperature, a very good idea 
of the efficiency of the plant can be obtained previous 
to making the engineering test. For example, in a 
test which the author made in connection with his 
students, the efficiency was increased from 58 to 70 
per cent, upon the results of the gas analysis alone. 



2 GAS AND FUEL ANALYSIS. 

To this end a representative sample must be collected 
according to the method about to be described. 

SAMPLING.* 

Before proceeding to take a sample of the gas, the 
plant — for example, a boiler setting — from which the 
gas is to be taken should be thoroughly inspected, 
and all apertures by which the air can enter, other than 
those so intended, carefully stopped up. This includes 
not only cracks in the setting and leaks about clean-out 
doors, but also the bricks and mortar of the setting 
itself; these are porous, and unless glazed or hard- 
burned, should be given a thin coat of size and also of 
whitewash. Material gains in economy have been 
effected by covering the whole setting with a thick 
coating of asbestos cement, protected by a coating of 
canvas, which was kept painted. 

The best place to take a sample from a fire tube 
boiler is in the uptake just as it leaves the boiler: in a 
water tube boiler from the last pass. Leakage from the 
damper should be avoided by inserting the tube on the 
grate side of the damper. The tube should be long 
enough to reach about halfway across the flue and pro- 
ject out about a foot from it, so that the gas may be 
cool that flows through the type. A suitable tube is 
then inserted air-tight and in the gas-duct, connected 
with the sampling or gas apparatus, and suction applied, 
thus drawing the gas out. Cork, putty, plaster of Paris, 
wet cotton-waste., or asbestos may be used to render the 

* See Bureau Mines Bulletin 97, " Sampling and Analyzing Flue 
Gases," 1915. 



INTRODUCTION AND METHODS OF SAMPLING. 3 

joint gas-tight. The place of insertion should be chosen 
where the gas will be most completely mixed and least 
contaminated with air. The oil-bath containing the 
thermometer is similarly inserted near the gas-tube, and 
the temperature read from time to time. 

1. Tubes. — The tubes usually employed are Bohe- 
mian-glass combustion tubing or water-cooled metal 
tubes; those of porcelain are also sometimes used. 
Glass and porcelain tubes when subjected to high tem- 
peratures must be previously warmed or gradually 
inserted: the former may be used up to temperatures 
of 6oo° C. (1112 F.). Uncooled metal tubes, other 
than those of platinum, should under no circumstances 
be used.* 




Fig. 1. — Gas-sampling Tube. 



The metal tube with the water cooling is made as 
shown in Fig. 1, c being a piece of brass pipe 3 feet 
long, ij inches outside diameter, b the same length, 
I inch in diameter, and a \ inch in diameter. The 

* Fischer, " Technologie der Brennstoffe," 1880, p. 221, states that 
the composition of a gaseous mixture was changed from 1.5 to 26.0 
per cent carbon dioxide, by the passage through an iron tube heated to a 
dull red heat, the carbonic oxide originally present reducing the iron 
oxide with the formation of carbon dioxide; this can take place at 250 . 
(Campbell " Manufacture of Iron and Steel, p. 53,") 



GAS AND FUEL ANALYSIS. 



water enters at d and leaves at e. The walls of the 
tubes are & inch thick. The joint at A should be 
brazed; the others may be soldered. 

Quartz tubes can be used in place of the water-cooled 
metal tubes and have the advantage that they require no 
previous warming. 

2. Apparatus for the Collection of Samples. — 
A convenient sampling apparatus is shown in Fig. 2. 




Fig. 2. — Sampling Apparatus. 

It may be made from a liter separatory funnel — in- 
stead of the bulb there shown — fitted with a rubber 
stopper carrying a tube passing to the bottom and a 
T tube; both of these, except where sulphur-con- 
taining gases are present, can advantageously be 



INTRODUCTION AND METHODS OF SAMPLING. 5 

made of -j^-inch lead pipe. The stopper should not 
be fastened down with wire between the tubes after 
the manner of wiring effervescent drinks, as this draws 
the rubber away from the tubes and occasions a leak. 
The fastening shown consists of a brass plate fitting 
upon the top of the stopper, provided with screws 
and nuts which pass through a wire around the neck 
of the separatory. A chain fastened to the plate serves 
as a convenient method of handling it. 

In using the apparatus, the bulb is filled with water 
by connecting the stem with the water-supply and 
opening one of the pinchcocks upon the T tube; the 
water thus entering from the bottom forces the air 
out before it. One branch of the T is connected with 
the sampling-tube and the other with the suction- 
pump, the stopcocks being open, and a current of gas 
drawn down into the pump; upon opening the cock 
upon the stem, the water runs out, drawing a small 
portion of the gas-current passing through the T after 
it into the bulb. It is then taken to a convenient 
place for analysis, the tube h connected with a head of 
water, a branch of the T i, with the gas apparatus, 
and a sample of gas forced over into the latter for 
analysis. 

Enough water should be left in the bulb to seal the 
stopcock on the bottom and prevent leakage. This 
apparatus is better adapted for the needs of the class- 
room than for actual practice, as it enables the same 
sample to be given to eight or ten students. As has 
been shown by several years' experience, the water 
exercises no appreciable solvent action upon the 
gaseous mixture in the time— about half an hour — 






GAS AND FUEL ANALYSIS. 



necessary to collect and distribute the samples. It is 
often necessary to attach about a yard of f-inch rubber 




Fig. 4. — Gas-tube. 



Fig. 3. — Sampling Apparatus for 
Mine-gases. 



tubing to the stem of the bulb to prevent air being sucked 
up through it when taking a sample. 

In the actual boiler-test it is preferable to insert a T 
instead of this apparatus in the gas-stream, connect the 



INTRODUCTION AND METHODS OF SAMPLING. 7 

gas apparatus to the free branch of this T, and draw the 
sample. In making connections with gas apparatus 
the air in the rubber connectors should be displaced 
with water by means of a medicine-dropper. 

In the Saxon coal-mines, zinc cans * of ten liters 
capacity, of the form shown in Fig. 3, are used by Wink- 
ler for sampling the mine-gases; they are carried down 
filled with water and this allowed to run out, and the 
gas thus obtained brought into the laboratory and anal- 
yzed. Small samples of gas may very well be taken 
in tubes of 100 cc. capacity like Fig. 4, the ends of which 
are closed with rubber connectors and glass plugs. Rub- 
ber bags are not to be recommended for the collection 
and storage of gas for analysis, as they permit of the 
diffusion of gases, notably hydrogen. 

3. Apparatus for Producing Suction. — I. Water- 
pumps — (a) Jet-pumps, depending for their action 
upon a considerable head of water, and (b) those depending 
rather upon a sufficient fall of water. 

(a) Jet- pumps. — The Richards jet pump f is shown in 
section in Fig. 5 and much resembles a boiler injector; it 
consists of a water-jet w, a constriction or waist a, a waste- 
tube 0, and a tube for the inspiration of air. The jet of 
water forms successive pistons across a, drawing the air in 
with it and is broken up into foam by the zigzag tube 0. 

This pump is known in Germany as Muencke's, and 
in England as Wing's: Chapman's pump is also a mod- 
ified form. 



* If used with gases containing C0 2? it attacks the zinc. Murmann, 
Oest. Ch. Ztg., 17, 69 (1914). 

t Richards, Am. Jour, of Science (3), 8, 412; Trans. Am. Inst. Min. 
Engrs., 6, 492 (1874). 



8 



GAS AND FUEL ANALYSIS. 



It may be easily constructed in glass, the jets pass- 
ing through rubber stoppers which are wired down, 




Fig. 5. — Richards' Jet-pump. Fig. 6. — Bunsen's Pump. 

thus admitting of adjustment to the conditions under 
which it has to work.* 



* The pump will also work well using steam. 



INTRODUCTION AND METHODS OF SAMPLING. g 

(b) Fall-pumps. — Bunsen's pump, Fig. 6, consists 
of a wide glass tube A, drawn out at the bottom for 
connection with a J-inch lead pipe b, and at the top 
for connection with c, the tube through which the air 
is drawn; this tube is usually fused in, although it 
may be connected with rubber; a is a rubber tube 
provided with screw cocks connected with the water- 
supply; d is connected with a mercury column, and 
the vessel B serves for the retention of any water 
which might be drawn back into the apparatus evac- 
uated. 

The tube b for the best results should be 32 feet in 
length, equal to the height of a column of water sup- 
ported by the atmosphere, although for the ordinary 
purposes of gas-sampling it may be shorter. 

When water is admitted through a it fills b, acting 
as a continually falling piston drawing the current 
of air through e and its connections. These vari- 
ous forms of water-pumps should give a vacuum 
represented by the height of the barometer less 
the tension of aqueous vapor at the temperature 




Fig. 7.— Steam Air-pump. 



at which they are used, or about 29 inches of 
mercury. 

II. Steam-pumps. — Kochinke describes the appa- 
ratus in use in the Muldner Hiitten in Freiberg, 



10 GAS AND hUEL ANALYSIS. 

shown at one-fifth size in Fig. 7. It consists of a 
glass tube drawn down to an opening 6 mm. in diam- 
eter; concentric with this, and held in place by the 
washer a, is the steam-jet 2 mm. in diameter, passing 
through the cork b> the cement c> and covering d. It 
is connected with the steam-pipe at g by webbed 
rubber tubing/; the air enters at e. This is said to 
give very good results and be economical in use of 
steam. 

In case neither water nor steam be available, 
recourse must be had to the ordinary rubber syringe- 
bulbs, provided with suitable valves, obtainable at any 
rubber store, or to a bottle aspirator. This consists of 
two one-gallon bottles, provided with doubly perfor- 
ated rubber stoppers, carrying tubes of glass or lead 
bent at right angles. In each bottle one of these tubes 
passes nearly to the bottom, and these are connected 
together by a piece of rubber tubing a yard long, 
carrying a screw pinchcock. The other tube in each 
case stops immediately under the stopper. Upon 
filling one of the bottles with water, inserting the 
stopper and blowing strongly through the short tube, 
water will fill the long tubes thus forming a siphon, 
and upon lowering the empty bottle, a current of air 
will be sucked in through the short tube originally 
blown into; this may be regulated by the screw 
pinchcock. 

In inserting the gas-sampling tube care should be 
taken not to insert it so close to the source of heat 
as to draw out the gases in a dissociated, i.e. partly 
decomposed, condition. 

In case of very smoky fuels it is well to filter the 



INTRODUCTION AND METHODS OF SAMPLING. II 

gases through rolls of fine wire gauze or asbestos ; in 
sucking them through a washing-bottle, the water 
may change the composition of the sample. 

Where a continuous sample is to be taken, the 
water in the containers should be replaced by strong 
brine. 



CHAPTER II. 
APPARATUS FOR THE ANALYSIS OF CHIMNEY-GASES. 

Gases are analyzed by absorbing the various con- 
stituents, and observing the diminution in volume: in 
case the gas be unabsorbable, as for example, methane, 
CH4, it is burned, and the carbon dioxide and water 
determined, from which the methane can be calcu- 
lated. 

In the writer's opinion the apparatus which is best 
adapted for this purpose is that of Orsat; it is readily 
portable, not liable to be broken, easy to manipulate, 
sufficiently accurate, and — in the modification about to 
be described — always ready for use, there being no 
stopcocks to stick fast. 

As the Bunte and Elliott apparatus are also used 
for this purpose, they too will be described. 

Fischer's apparatus, using mercury, is rather too 
difficult for the average engineer; Hempel's, Elliott's 
or Morehead's apparatus for the analysis of illuminating- 
gas might also be used; it is, however, not customary. 

ORSAT APPARATUS. 

Description. — The apparatus Fig. 8, is enclosed 
in a case to permit of transportation from place to 
place; furthermore, the measuring- tube is jacketed 

12 



ANALYSIS OF CHIMNEY-GASES. 



13 



with water to prevent changes of temperature affect- 
ing the gas-volume. The apparatus consists essen- 
tially of the le veiling-bottle A, the burette B, the 
pipettes P', P" } P' n \ and the connecting tube or 
" header " T. 
Pipette P r is filled with potassium (or sodium) hy- 




Fig. 8.— Orsat's Gas Apparatus. 



droxide solution (see Reagents) so that when it is 
drawn up into the front arm, about half an inch in 
depth is left in the rear arm. Pipettes P" and P f,f 
are similarly filled with potassium (or sodium) pyro- 
gallate and cuprous chloride solution respectively. 
These reagents require to be protected from the oxygen 
of the air by collapsible rubber bags. As the oxygen 



14 CAS AXD FUEL ANALYSIS. 

in the air over the reagent is absorbed, a diminution 
in pressure takes place, rendering it difficult to bring the 
reagent to the point on the stem: the obvious remedy 
is to remove the bag temporarily and adjust the reagent 
as shown below (manipulation): only about | inch 
should be in the rear arm. When the apparatus is first 
set up, one or two blank analyses should be made, to 
saturate the water and reagents with the gases. For 
example the potassium hydroxide absorbs carbon di- 
oxide, it also absorbs about 3 cc. of oxygen, 2 cc. of car- 
bon monoxide and 1.5 cc. of nitrogen by virtue of the 
100 cc. of water which it contains. A change of tem- 
perature of i° makes a change of 0.36% of the volume 
of the gas; a change of pressure of 1 mm. produces 0.13% 
change in volume. 

Manipulation.— The reagent in the pipettes should 
be adjusted in the capillary tubes to a point on the 
stem about midway between the top of the pipette 
and the rubber connector. This is effected by open- 
ing wide the pinchcock upon the connector, the 
bottle being on the table, and very gradually lower- 
ing the bottle until the reagent is brought to the point 
above indicated. Six inches of the tubing used corre- 
spond to but 0.1 cc, so that an error of half an inch 
in adjustment of the reagent is without influence 
upon the accuracy of the result. The reagents having 
been thus adjusted, the burette and connecting tube 
are completely filled with water by opening d and 
raising the leveling-bottle. The apparatus is now 
ready to receive a sample of gas (or air for prac- 
tice). In case a flue-gas is to be analyzed discon- 
nected with i, Fig. 2, A lowered and about 102 cc. 



ANALYSIS OF CHIMNEY-GASES. 15 

of the gas forced over by opening h; or d may 
be connected with aT joint in the gas-stream; the 
burette after filling is allowed to drain one minute by 
the sand-glass, c snapped upon its rubber tube, and 
the bottle A raised to the top of the apparatus. By 
gradually opening c the water is allowed to run into 
the burette until the lower meniscus stands upon the 
100 or o mark (according to the graduation of the 
apparatus). The gas taken is thus compressed into 
the space occupied by 100 cc, and by opening d the 
excess escapes. Open c and bring the level of the 
water in the bottle to the same level as the water in the 
burette and take the reading, which should be 100 cc. 
Special attention is called to this method of reading: 
if the bottle be raised, the gas is compressed; if 
lowered, it is expanded. 

Determination of Carbon Dioxide. — The gas to be 
analyzed is invariably passed first into pipette P', con- 
taining potassium hydrate for the absorption of carbon 
dioxide, by opening e and raising^. The gas dis- 
places the reagent in the front part of the pipette, 
laying bare the tubes contained in it, which being 
covered with the reagent present a large absorptive 
surface to the gas; the reagent moves into the rear 
arm of the pipette, displacing the air over it into the 
flexible rubber bag which prevents its diffusion into 
the air. The gas is forced in and out of the pipette 
by raising and lowering^, the reagent finally brought 
approximately to its initial point on the stem of the 
pipette, the burette allowed to drain one minute, and 
the reading taken. The difference between this and 
the initial reading represents the cubic centimeters of 



16 GAS AND FUEL ANALYSIS. 

carbon dioxide present in the gas. To be certain that 
all the carbon dioxide is removed, the gas should be 
passed a second time into P' and the reading taken 
as before; these readings should agree within o.i per 
cent. 

Determination of Oxygen.— The residue from the 
absorption of carbon dioxide is passed into the second 
pipette, P" y containing an alkaline solution of potas- 
sium pyrogallate, until no further absorption will take 
place. The difference between the reading obtained 
and that after the absorption of carbon dioxide, repre- 
sents the number of cubic centimeters of oxygen 
present. 

Determination of Carbonic Oxide. — The residue 
from the absorption of oxygen is passed into the third 
pipette, P'" , containing cuprous chloride, until no 
further absorption takes place; that is, in this case 
until readings agreeing exactly (not merely to o. i) are 
obtained. The difference between the reading thus 
obtained and that after the absorption of oxygen, 
represents the number of cubic centimeters of carbonic 
oxide present. 

Determination of Nitrogen and Hydrocarbons. — 
The residue left after all absorptions have been made 
may consist, in addition to nitrogen, the principal 
constituent, of hydrocarbons and hydrogen. Their 
determination is difficult for the inexperienced, and, 
if desired, a sample of the flue-gas should be taken, 
leaving as little water in the apparatus as possible, 
and sent to a competent chemist for analysis. 

Accuracy. — The apparatus gives results accurate 
to 2 of i per cent. 



ANALYSIS OF CHIMNEY-GASES. 17 

Time Required. — About twenty minutes are re- 
quired for an analysis ; two may be made in twenty- 
five minutes, using two apparatus. 

Notes. — The method of adjusting the reagents is 
the only one which has been found satisfactory ; if 
the bottle be placed at a lower level and an attempt 
made to shut the pinchcock c upon the connector 
at the proper time, it will almost invariably result in 
failure. 

The process of obtaining 100 cc. of gas is exactly 
analagous to filling a measure heaping full of grain and 
striking off the excess with a straight-edge; it saves 
arithmetical work, as cubic centimeters read off repre- 
sent percent directly. 

It often happens when e is opened, c being closed, 
that the reagent in P' drops, due not to a leak as is 
usually supposed, but to the weight of the column of 
the reagent expanding the gas. 

The object of the rubber bags is to prevent the 
access of air to the reagents, those in P" and P'" 
absorbing oxygen with great avidity, and hence if 
freely exposed to the air would soon become use- 
less. 

Carbon dioxide is always the first gas to be re- 
moved from a gaseous mixture. In the case of air 
the percentage present is so small, 0.08 to o. 1, 
as scarcely to be seen with this apparatus. It is 
important to use the reagents in the order given ; 
if by mistake the gas be passed into the second 
pipette, it will absorb not only oxygen, for which 
it is intended, but also carbon dioxide; similarly 
if the gas be passed into the third pipette, it will 



18 GAS AND FUEL ANALYSIS. 

absorb not only carbonic oxide, but also oxygen 
as well. 

The use of pinchcocks and rubber tubes, original 
with the author, although recommended by Naef,* is 
considered by Fischer, f to be inaccurate. The ex- 
perience of the author, however, does not support 
this assertion, as they have been found to be fully 
as accurate as glass stopcocks, and very much less 
troublesome and expensive. 

In case any potassium hydrate or pyrogallate be 
sucked over into the tube T^or water in A, the analysis 
is not spoiled, but may be proceeded with by connect- 
ing on water at d, opening this cock, and allowing the 
water to wash the tubes out thoroughly. The addi- 
tion of a little hydrochloric acid to the water in the 
bottle A will neutralize the hydrate or pyrogallate, and 
the washing may be postponed until convenient. 

After each analysis the number of cubic centimeters 
of oxygen and carbonic oxide should be set down upon 
the ground-glass slip provided for the purpose. By 
adding these numbers and subtracting their sum from 
the absorption capacity (see Reagents) of each reagent, 
the condition of the apparatus is known at any time, 
and the reagent can be renewed in season to prevent 
incorrect analyses. 

BUNTE APPARATUS. 

Description. — The apparatus Fig. 9 consists of a 
burette — bulbed to avoid extreme length — provided 

* Wagner's Jahresb. 1885, p. 423. 

f Technologie d. Brennstoffe, foot note p. 295. 



ANALYSIS OF CHIMNEY-GASES. 



19 



at the top with a funnel i^and three-way cock/, and 
a cock / at the bottom. These stopcocks are best 
of the Greiner and Friedrichs obliquely bored form. 
The burette is supported upon a retort- 
stand with a spring clamp. 

A " suction-bottle " S, an 8-oz. wide- 
mouthed bottle, fitted similarly to a 
wash-bottle, except that the delivery- 
tube is straight and is fitted with a 
four-inch piece of J-inch black rubber 
tubing, serves to withdraw the re- 
agents and water when necessary Q A 
reservoir to contain water at the tem- 
perature of the room, fitted with a long 
rubber tube, should be provided for 
washing out the reagents and filling 
the burette. 

Manipulation. — Before using the 
apparatus, the keys of the stopcocks 
should be taken out, wiped dry, to- 
gether with their seats, and sparingly 
smeared with vaseline or a mixture of 
vaseline and tallow and replaced. The Fig. 9.— Bunte's 
completeness of the lubrication can be Gas Apparatus - 
judged by the transparency of the joint, a thoroughly 
lubricated joint showing no ground glass. The 
burette is filled with water by attaching the rubber 
tube to the tip at / and opening the stopcocks at the 
top and bottom ; j is connected with the source whence 
the gas is to be taken, turned to communicate with 
the burette and opened, about 102 cc. of gas allowed 
to run in, and j and /closed. 



n 



20 GAS AND FUEL^ANALYSIS. 

The cup F is filled with water to the 25-cc. mark, j 
turned to establish communication between it and the 
burette, the burette allowed to drain one minute by 
the sand-glass, and the reading taken, the cup being 
refilled to the mark if necessary. The readings are 
thus taken under the same pressure each time, i.e., 
this column of water plus the height of the barometer; 
and as the latter is practically constant during the 
analysis, no correction need be applied, it being within 
the limits of error. 

Determination of Carbon Dioxide. — The " suc- 
tion-bottle " is connected with the tip of the burette, 
/ opened, and the water carefully sucked out nearly to 
/. The bottle is now disconnected, the burette dis- 
mounted from its clamp, using the cup as a handle, 
and the 25 cc. of water turned out. The tip is 
immersed under potassium hydrate contained in the 
No. 3 porcelain dish, and the cock / opened, then 
closed, and the tip wiped clean with a piece of cloth. 
The burette is now shaken, holding it by the tip and 
the cup, the thumbs resting upon j and /; more 
reagent is introduced, the absorption of the gas caus- 
ing a diminished pressure, and the operation repeated 
until no change takes place. The cup is now filled 
with water, j opened, and the reagent completely 
washed out into an ordinary tumbler placed beneath 
the burette. Four times filling of F should be suffi- 
cient for this purpose. The cup is now filled to the 
25-cc. mark, j opened, and the reading taken as 
before. 

The difference between this reading and the initial 
represents the number of cubic centimeters of carbon 



ANALYSIS OF CHIMNEY-GASES. 21 

dioxide; this divided by the volume of the gas taken 
gives the per cent of this constituent. 

Determination of Oxygen. — The water is again 
sucked out, and potassium pyrogallate solution intro- 
duced, similarly to potassium hydrate; this is dis- 
placed by water, and the reading taken as before. 
The difference between this and the last reading is the 
volume of oxygen present. 

Determination of Carbonic Oxide. — The water is 
removed for a third time, and acid cuprous chloride 
solution introduced and the absorption made as before; 
this is washed out, first with water containing a little 
hydrochloric acid to dissolve the white cuprous chlo- 
ride which is precipitated by the addition of water, 
and finally with pure water, and the reading taken as 
before. The difference between this and the preced- 
ing gives the volume of carbonic oxide present. 

Notes. — Especial care should be taken not to grasp 
the burette by the bulb, as this warms the gas and 
renders the readings inaccurate. The stopcocks can 
conveniently be kept in the burette by elastic bands 
of suitable size. When the apparatus is put away for 
any considerable time, a piece of paper should be 
inserted between the key and socket of each stopcock 
to prevent the former from sticking fast. To ascer- 
tain when the absorption is complete, the burette is 
mounted in its clamp and allowed to drain until the 
meniscus is stationary, the dish containing the reagent 
raised until the tip is covered, /opened, and any change 
in level noted. If the meniscus rises, the absorption 
is incomplete and must be continued; if it remains 
stationary or falls, the absorption may be regarded as 



2 2 GAS AND FUEL ANALYSIS. 

finished. In case the grease from the stopcocks 
becomes troublesome inside the burette, it may be 
removed by dissolving it in chloroform and washing 
out with alcohol and then with water. The object in 
sucking the water not quite down to /, thus leaving a 
little water in the burette, is to discover if / leaks, the 
air rushing in causes bubbles. 

The object in washing out each reagent and taking 
all readings over water is to obviate corrections for 
the tension of aqueous vapor over potassium hydrate, 
hydrochloric acid, or any of the reagents which might 
be employed. The tension of aqueous vapor over 
seven per cent caustic soda is less than over water. 

Accuracy and Time Required. — The apparatus is 
rather difficult to manipulate, but fairly rapid — about 
twenty-five minutes being required for an analysis — 
and accurate to one tenth of one per cent. 

ELLIOTT APPARATUS. 

Description. — The apparatus Fig. 10 consists of a 
burette holding ioo cc. graduated in tenths of a cubic 
centimeter and bulbed like the Bunte apparatus — the 
bulb holding about 30 cc. ; it is connected with a 
levelling-bottle similar to the Orsat apparatus. The 
top of the burette ends in a capillary stopcock, the 
stem of which is ground square to admit of close con- 
nection with the " laboratory vessel,* ' an ungraduated 
tube similar to the burette, except of 125 cc. capacity. 
The top of this "vessel " is also closed with a capil- 
lary stopcock, carrying by a ground-glass joint a 
thistle-tube F, for the introduction of the reagents. 
The lower end of this " vessel M is closed by a rubber 



ANALYSIS OF CHIMNEY-GASES. 



23 



\=Q 



^y- 



stopper carrying a three-way cock 0, and connected 
with a levelling-bottle D. The 
burette and vessel are held upon a 
block of wood — supported by a ring 
stand — by fine copper wire tight- 
ened by violin keys. 

Manipulation. — The ground-glass 
joints are lubricated as in the Bunte 
apparatus. The levelling-bottles are 
filled with water, the stopcocks 
opened, and the bottles raised until 
the water flows through the stop- 
cocks m and n. m is connected 
with the source whence the gas to 
be analyzed is to be taken, n closed, 
D lowered and rather more than 100 
cc. drawn in, and m closed, n is 
opened, D raised and E lowered, 
nearly 100 cc. of gas introduced, 
and n closed; by opening m and 
raising D the remainder of the gas 
is allowed to escape, the tubes being 
filled with water and m closed, n is 
opened and the water brought to 
the reference-mark; the burette is 
allowed to drain one minute, the 
level of the water in E is brought 
to the same level as in the burette, 
and the reading taken. 

Determination of Carbon Dioxide. — By raising E> 
opening n y and lowering D, the gas is passed over into 
the laboratory vessel; F is filled within half an inch 



f 



FiCx. 10. — Elliott 
Gas Apparatus. 



24 GAS AND FUEL ANALYSIS. 

of the top with potassium hydrate, o closed, ;;/ opened, 
and the reagent allowed to slowly trickle in. A No. 3 
evaporating-dish is placed under <?, and this turned to 
allow the liquid in the laboratory vessel to run into 
the dish. At first this is mainly water, and may be 
thrown away; later it becomes diluted reagent and 
may be returned to the thistle-tube. When the 
depth of the reagent in the thistle-tube has lowered 
to half an inch, it should be refilled either with fresh 
or the diluted reagent and allowed to run in until the 
absorption is judged to be complete, and the gas 
passed back into the burette for measurement. To 
this end close and then m, raise £, open n, and 
force some pure water into the laboratory vessel, thus 
rinsing out the capillary tube. Now raise D and lower 
E y shutting n when the liquid has arrived at the refer- 
ence-mark. The burette is allowed to drain a minute, 
the level of the water in the bottle E brought to the 
same level as the water in the burette, and the reading 
taken. 

Determination of Oxygen. — The manipulation is 
the same as in the preceding determination, potassium 
pyrogallate being substituted for potassium hydrate; 
the apparatus requiring no washing out. 

Determination of Carbonic Oxide. — The labora- 
tory vessel, thistle-tube, and bottle if necessary, are 
washed free from potassium pyrogallate and the 
absorption made with acid cuprous chloride similarly 
to the determination of carbon dioxide. The white 
precipitate of cuprous chloride may be dissolved by 
hydrochloric acid. 



ANALYSIS OF CHIMNEY-GASES. 25 

Accuracy and Time Required.— The apparatus is 
as accurate for absorptions as that of Orsat; it is 
stated to be much more rapid — a claim which the writer 
cannot substantiate. It is not as portable, is more 
fragile, and more troublesome to manipulate, and as 
the burette is not jacketed it is liable to be affected 
by changes of temperature. 

Notes. — In case at any time it is desired to stop 
the influx of reagent, o should be closed first and 
then m\ the reason being that the absorption may 
be so rapid as to suck air in through o, m being 
closed. 

The stopcock should be so adjusted as to cause the 
reagent to spread itself as completely as possible over 
the sides of the burette. 

By the addition of an explosion-tube it is much used 
for the analysis of illuminating-gas,* bromine being 
used to absorb the " illuminants." Winkler f states 
that this absorption is incomplete; later work by 
Treadwell and Stokes, and also Korbuly,f has shown 
that bromine water, by a purely physical solution, 
does absorb the " illuminants " completely ; Hempel § 
states that explosions of hydrocarbons made over 
water are inaccurate, so that the apparatus can be 
depended upon to give results upon methane and 
hydrogen only within about 2 per cent. It is, how- 
ever, very rapid, a complete analysis of illuminating 
gas can be made with it in fifty-minutes. 

* Mackintosh, Am. Chem. Jour. 9, 294. 

t Zeit. f. Anal. Chem. 28, 286. 

\ Treadwe-U's Quan. Analysis (Hall's translation), p. 569. 

§ Gasanalytische Methoden, p. 102. 



26 GAS AND FUEL ANALYSIS. 



CARBONIC ACID INDICATORS. 

These usually depend upon the principle of collecting 
100 cc. of the gas, causing it to pass through a suitable 
absorber and collecting the residue in a bell which floats 
to a greater or less height according to the residual vol- 
ume. The fluctuations of this bell are recorded after 
the usual manner of self-registering barometers or ther- 
mometers; the usual time for this analysis and record is 
five minutes. The Gas-composimeter of Uehling * de- 
pends upon the laws governing the flow of gases through 
small apertures. 

They are difficult to adjust and keep in adjustment, 
requiring to be checked frequently by the Orsat appa- 
ratus, and are expensive. They are, however, worth all 
they cost, both in money and trouble in using, and have 
come to be regarded almost as much a part of boiler- 
room equipment as a steam gage. They will repay their 
cost in a short time. Their indications are within about 
half of I per cent of those given by the chemical appa- 
ratus. Only the presence of carbon dioxide is indicated 
by them, although by the addition of combustion apparatus 
carbon monoxide is also registered. 

References. — For the analysis of flue and chimney 
gases the following papers of the Bureau of Mines are 
recommended : 

Apparatus for the Exact Analysis of Flue Gas. Burrell 
and Seibert, Technical Paper 31, 19 13. 

Sampling and Analyzing Flue Gases. Kreisinger and 
Ovitz. Bull. No. 97, 1915. 

* Gill, " Engine Room Chemistry." 



ANALYSIS OF CHIMNEY-GASES, 



27 



Instruments for Recording Carbon Dioxide in Flue 
Gases. Barkley and Flagg. Bull. No. 91, 1916. 

Use of the Interferometer in Gas Analysis. Seibert and 
Harpster, Technical Papers, 185, 198. 
- Combustion and Flue Gas Analysis. Technical Paper, 
219. 



CHAPTER III. 
MEASUREMENT OF TEMPERATURE. 

In the majority of cases, the ordinary mercurial 
thermometer will serve to determine the temperature 
of the chimney-gases. It should not be inserted naked 
into the flue, but be protected by a bath of cylinder, 
or raw linseed oil, or even sea sand, contained in a 
brass or iron tube. These tubes may be half an inch 
inside diameter and two to three feet in length. Tem- 
peratures as high as 62 5 ° C. have been observed in chim- 
neys: this lasts of course but for a moment, but would 
be sufficient to burst the unprotected thermometer. 

For the observation of higher temperatures, recourse 
must be had to the " high- temperature thermom- 
eters/ ' filled with carbon dioxide or nitrogen under a 
pressure of about one hundred pounds, giving readings 
to 550 C* These may be obtained of the dealers in 
chemical apparatus; some require no bath, being pro- 
vided with a mercury-bath carefully contained in a 
steel tube, and the whole enclosed in a bronze tube.f 

These thermometers should be tested from time to 
time either by comparison with a standard, or by inser- 

* H. J. Green of Brooklyn, N. Y., makes thermometers about three 
feet long, the scale occupying about one foot, thus avoiding the neces- 
sity of withdrawing the thermometer from the bath for reading. 

| Hohmann Special Thermometers, made by Hohmann and Maurer 
Division, Taylor Instrument Co., Rochester, N. Y. 

28 



MEASUREMENT OF TEMPERATURE. 29 

tion in various baths of a definite temperature. Some 
of the substances used for these baths are: water, 
boiling-point ioo°; naphthalene, Bpt. 218 ; tin, 
melting-point 231 ; benzophenon, Bpt. 306 ; and 
sulphur,* Bpt. 445 . Care should be taken that the 
bulb of the thermometer does not dip into the boil- 
ing liquid, but only into the vapor, and that the 
stem exposure be as nearly as possible that in actual 
use. 

For the measurement of temperatures beyond the 
range of these thermometers, or even below it, in many 
cases, the Le Chatelier thermo-electric pyrometer may 
be used. This consists of a thermo-couple formed by 
the junction of a platinum and platinum-10% rhodium 
wire, passing through fire-clay tubes in a porcelain or 
iron envelope and connected with a galvanometer. 
The hotter the junction is heated the greater the cur- 
rent or electro-motive force. 

If the couple be connected to a millivoltmeter, the 
temperature of the heated junction can be readily 
measured. This couple and junction may be cali- 
brated by exposing it to several known temperatures. 
The boiling-point of sulphur, the melting-point of zinc 
419 , aluminum 658 , and copper 1083 , may be used 
for this calibration. Since there is always a small 
electro-motive force at the cold junction where the ther- 
mocouple joins the lead-wires, or to the instrument 

* In testing the Hohmann thermometers in sulphur-vapor, the 
bronze tube should be prevented from corrosion by the vapor by a 
quartz envelope. 

t Written in collaboration with his colleague Prof. Charles L. Norton, 
whose assistance is thankfully acknowledged. 



30 GAS AND FUEL ANALYSIS. 

itself, a correction for the cold junction or some com- 
pensation device is needed. 

For most temperatures up to noo°, couples of the 
" base metals " (Ni, Cr, Co, or Fe) may be used instead 
of platinum. There are a number of such alloys which 
have a large electro-motive force, the temperature varia- 
tion of which bears nearly a straight line relation to the 
electro-motive force. These are relatively inexpensive, 
strong, and for general pyrometric work are very satis- 
factory. 

Both the base-metal couples and the platinum couples 
need to be protected from chemical action by sealing or 
enclosing them in tubes of steel, porcelain, quartz or 
alundum. Protection tubes of these materials can be 
had in various sizes from the makers of pyrometers and 
potentiometers, so that with a multiple switch, per- 
manent records can be made of the variations in tem- 
perature at a considerable number of points at one time. 

For measuring the temperature of furnaces and fire 
boxes, optical pyrometers may be used. They are 
instruments for measuring the intensity of heat radia- 
tion given out by the heated body. Some of these 
instruments measure the total radiation from the 
hot body in the direction of the instrument. Others 
measure the temperature by determining the brightness 
or color of the hot body. A number of such instru- 
ments are now on the market. They are accurate and 
easy to use. For an adequate discussion of pyrometry 
see " Measurement of High Temperatures " by Burgess 
and Le Chatelier, or " Pyrometry Volume, April, 1920," 
of the American Institute of Mining and Metallurgical 
Engineers. 



MEASUREMENT OF TEMPERATURE. 



31 



An error of 5 ° in the .reading of the thermometer 
affects the final result in the case of a chimney gas by 
about 20 calories. 

In case neither of these methods be available nor 
applicable, as in case of a locomotive smoke stack, use 







Fig. 11. — Melting-point Boxes. 

may be made of the melting-points of certain metals or 
salts contained in small cast-iron boxes, Fig. n. The 
melting-points of certain metals and salts are given in 
Table X, Appendix. See also Bull. 145, Bur. Mines, 
" Measuring the Temperature of Gases in Boiler Set- 
tings (1918). 



CHAPTER IV. 

CALCULATIONS. 

As has been already stated in the Introduction, the 
object of analyzing the flue-gases is to ascertain, first, 
the completeness of the combustion, especially the 
amount of air which has been used or the " pounds of 
air per pound of coal," and second, the amount of 
heat passing up chimney. 

A. VOLUMETRIC OR MOLAL CALCULATION.* 

I. To Ascertain the Pounds of Air per Pound of 
Coal — The analysis of a chimney gas during a boiler 
test at the Rogers Building was as follows: 

C0 2 11.5%, 2 74%, CO 0.9%, N 2 80.2%. The 
coal was of the following f composition: Moisture 
1.5%, carbon 83% (of which but 80% burned, 3% going 
into the ash) hydrogen 2.5%, ash 11.4%, sulphur 1.2%, 
oxygen and nitrogen (by difference) 0.4%. The table 
on page 33 shows the composition of the gas in more 
detail; for other data consult Table VIII, Appendix. 



* The author hereby gratefully acknowledges the assistance of his 
colleague, Prof. Sherrill, in this calculation. 

f For the method of analysis see pages 84 and 85. 

32 



CALCULATIONS. 



33 



COMPOSITION OF THE CHIilXEY GAS (lOO MOLS DRY GAS) 



Gases. 


Mol % 
or No. 
of Mols. 


Wt. grams, Mols. 


Total Mols 

free and 

Combined 

2 . 


No. of 
Atomic 
Wts. Com- 
bined C. 


Wt. c. 

Burned. 


Grms. 


C0 2 

CO 

o 2 

N, 


"-5 

0.9 

7-4 
80.2 


11.5X44= 5°6-° 
0.9X28= 25.2 
7.4X32= 236.8 

80.2X28 = 2245.6 


n-5 

o.45 
7-4 


"•5 

0.9 


II. 5X12 
0.9X12 


138.O 
10.8 




100. 


3013.6 


19-35 


12.4 




148.8 



The weight of coal corresponding to this 148.8 grms. 
of carbon is - ^~ X 100 = 186.1 grms. 



80 



80.2 , 



80.2 mols. nitrogen = -^X 100 = 101.4 mols. air. 
79.1 

101.4 mols. air weigh 101.4X28.95 grms. = 2936.8 grms., 

then the pounds of air per pound of coal are — ——- = 

15.78. 
2. To Ascertain the Quantity of Heat Passing 

Up Chimney.— The heating value of the coal was 7220 
calories per kilo : the mean specific heat of the chimney 
gases is 0.24: the temperature of the incoming air was 
25 C, of the chimney gases was 275 C. ; a rise of 
250 C. 

One kilo of coal furnishes 0.8 kilo of carbon and this 
requires 15.78 kilos of air to burn it, generating 16.58 
kilos of dry chimney gases. The heat these carry off is 
16.58X0.24X250 = 995 calories. 

We have taken no cognizance of the water vapor 
passing up the stack: this comes from (a) the moisture 



34 GAS AND FUEL ANALYSIS, 

in the coal; (b) the hydrogen in the coal, and (c) the 
moisture in the air. 

(a) Moisture in coal, 1.5% = .015 kg. 

(b) The increase in the per cent of nitrogen in the 
gases over that in the air (79.1), is due to the condensa- 
tion of the steam coming from the burning of the hydro- 
gen in the coal: 100 volumes of air contain 79.1 vol- 
umes of nitrogen which has in the chimney gas become 

80.2. The volume of the gas is ^~ = 98.6% of the origi- 

802 

nal volume of air: or 1.4 of the 20.9 volumes of oxygen 

have combined with (2.8 volumes of) hydrogen to form 

2.8 mols. of water: this weighs 2.8X18 = 50.4 grms. 

This comes from 186. 1 grms. coal as in 1 oris 27.1 grms. 

per 100. From a kilo of coal then 0.271 kilo of water 

are formed. 

(c) Moisture in the air: there were 15.78 kilos of air 

per kilo of coal (1) or 5 ' 7 =12.20 cu. meters; this was 

1.294 

50 per cent saturated with moisture and contained 

(Table 1, Appendix) 22.9 grms. if saturated. 

12. 2 = 22. 9X0.5 = .139 kilo. 

The water vapor is, (a) .01 5 + (6) .2ji + (c) .139 = 425 
kg. This carries off .425X480X250 = 51 calories. The 
heat lost is 995 + 51 = 1046 calories: this divided by 
7220, the heating value of the coal, is 14.48 %. That 
is 1448% of the heating value of the coal goes up the 
chimney. 

Ratio of Air Used to that Theoretically Necessary. — 
We note from the Table " Composition of the Chimney 
Gas," that there were 236.8 grams of oxygen passing 



CALCULATIONS. 35 

through the grate unused, this corresponds to 1025 grms. 
of air: this corresponds to — -^ =5.51 pounds of air 

per pound of coal: 15.78 pounds of air per pound of 
coal — 5.51 = 10.27 pounds of air actually used to burn a 

pound of coal. The ratio is ' =1.536 of air used, to 

10.27 

air theoretically necessary as against 1.533, p. 39. 

B. GRAVIMETRIC CALCULATION. 

I. To Ascertain the Number of Pounds of Air 
per Pound of Coal.— A chimney.gas gave 11.5% C0 2 , 
7.4 0, 0.9% CO., and 80.2% N. Data: atomic weights, 
= i6, C = i2; weight liter C02 = 1.966 grms., of 
N 1. 251 grms. of CO, 1.251 grms. Find the number of 
grams of each constituent in 100 liters of the furnace- 
gas, and from this the weight of carbon and weight of 
oxygen. 11. 5 (liters C02)Xi-97 (wt. liter CO2) = 

22.66 grms. CO2; now —(-^~r ) of this is oxygen = 

16.48 grms., 6.18 grms. is carbon. The weight of 
free nitrogen is 80.2X1.251 = 100.3 grms. The weight 
of carbon and oxygen in the carbonic oxide is 0.9 X 

1.25 = 1.12 grms. CO. Now -7: (7^-) is oxygen or 0.64 

grm., and 0.48 grm. is carbon. There are then pres- 
ent in 100 liters of the gas 100.3 gnns. nitrogen and 
6.66 grms. carbon; corresponding to 130.5 grms. air 
to 6.66 grms. carbon, air being 23.1% oxygen by 

weight; or 19.59 jL [ ^ r P er fL ' [ carbon. If 
the coal be 83% carbon, this figure must be diminished 



36 GAS AND FUEL ANALYSIS. 

accordingly, giving in this case 15.66 lbs. air per lb. 
of coal. A gave 15.78, p. 33. Theory requires 11.54 
lbs. air per lb. of carbon, but in practice the best results 
are obtained by increasing this from 30% to 100%.* 

2, To Ascertain the Quantity of Heat Passing 
up Chimney — Determine the volume of gas generated 
from 1 kilo of coal when burned so as to produce the 
gas the analysis of which has just been made according 
to the directions given. The chemical analysis of the 
coal is as follows: moisture 1.5%, sulphur 1.2%, car- 
bon 83%, hydrogen 2.5%, ash 11.4%, oxygen and 
nitrogen (by difference) 0.4%. Then there are in 
1 kilo of coal 830 grms. carbon, of this suppose but 
800 to be burned, the remaining 30 grms. going into the 
ash; of the 800 grms. 618/666 or 742 grms. produced 
carbon dioxide, and 48/666 or 58 grms. produced car- 
bonic oxide. From 6.18 grms. carbon were produced 
1 1.5 liters carbon dioxide in the problem in 1; hence 
742 grms. would furnish 1381 liters. 6.18 : 742 :: 11. 5 : y. 
y = 1381. Similarly 58 grms. carbon would furnish 109.0 
liters carbonic oxide. 0.48 : 58:10.90 : z. z = 109.0. 
The volume of oxygen can be found by the pro- 
portion n.s(% C0 2 ): 74(%0) •: 13.81 : #.# = 888 liters. 
In the same maner the nitrogen is found to be 
9631 liters. 11. 5 : 80.2 :: 1381 : u. ^ = 9631. One kilo 
of coal under these conditions furnishes 1.381 cu. meters 
carbon dioxide, 0.109 c. m. carbonic oxide, 0888 c. m. 
oxygen, and 9.631 c. m. nitrogen. 

The quantity of heat carried off by each gas is its 
rise of temperature X its weight X its specific heat. 

* Scheurer-Kestner, Jour. Soc. Chem. Industry, 7, 616. 0.75 lb. 
per 1000 B.t.u. Xisbet, Power, 36, 995 (191 2). Kent, id., 43, 454 (1916). 



CALCULATIONS. 37 

The specific heats of the various gases are shown in 
the table below, and for facility in calculation, a column 
is given obtained by multiplying the weight by the 
specific heat; multiplying the volumes obtained in the 
previous calculation by the numbers in this column 
and by the rise in temperature gives the number of 
calories (C) that each gas carries away. 

TABLE OF SPECIFIC HEATS OF VARIOUS GASES.* 

Name of Gas. Sp. Heat. 

Carbon dioxide (io°-35o°). . o. 234 

* * monoxide o . 245 

Oxygen 0.217 

Nitrogen o . 244 

Aqueous vapor o . 480 

In the test the average temperature of the escaping 
gases was 275 C; that of the air entering the grate 
was 2 5 C, a rise of temperature of 250 C. As shown 
by the wet-and-dry-bulb thermometer, the air was 
50 per cent saturated with moisture. 

The calculation of the heat carried away is then for: 

Cu. m. c. 

Carbon dioxide 1.381X250X0.463 = 160.0 

Carbonic oxide 0.109X" Xo.3o8= 8.4 

Oxygen 0.888X " Xo.3ii = 69.1 

Nitrogen 9.631X " Xo. 306 = 737.0 



Wt. of Cu. M. 


Sp. HeatX 




Kg. 


Wt. of Cu. M. 


Log 


I.97 


0.463 


9.6656 


1. 26 


0.308 


9.4886 


i-43 


0.311 


9.4928 


1.26 


0.306 


9.4857 


0.80 


O.387 


9.5877 



Total 12.009 974-5 

There is, however, another gas passing up chimney 
of which we have taken no cognizance, namely, water- 

* Fischer, Tech. d. Brennstoff, p. 267. 



38 GAS AND FUEL ANALYSIS. 

vapor; this comes from the moisture in the coal, from 
the combustion of hydrogen in the coal, and from the 
air entering the grate; its volume is calculated as 
follows: 

The moisture in the coal as found by chemical anal- 
ysis was 1.5% =0.015 kg.; the hydrogen in the coal was 
2.5% = 0.025 kg. The amount of water this forms 
when burned is nine times its weight, 0.025 kg.X9 = 
0.225 kg. The moisture in the air entering the grate 
would be, if completely saturated, 22.9 grams per cubic 
meter, as shown by Table I; it was, however, but 50% 
saturated. The quantity is then, the volume of air 
used per kilogram of coal X moisture contained in it, 
or 11.955X22.9X0.50 = 0.137 kg. The volume of air 
used is the volume of gases generated 12.009 cu - meters 
(p. 37) less one-half the carbonic oxide .054 cu. m. 
The weight of aqueous vapor passing up chimney per 
kilogram of coal is 0.015+0.225+0.137 = 0.377 kg.; 
the quantity of heat that this carries off is 0.377 X 
250X0.480 = 45.2 C. The total quantity of heat 
passing up chimney is then 1019.7 C. The heat of 
combustion of this coal as found by Mahler's calori- 
metric bomb was 7220 C; hence the percentage of 
heat carried off. is 1020/7220 = 14.1%. 

Rapid Methods of Calculation. 

The preceding calculations though correct are tedious, 
so much so, as to almost preclude their use for an hourly 
observation of the firing. They should be employed, 
however, in making the final calculation of a boiler-test, 
using the averages obtained. 



CALCULATIONS. 3Q 

Shields * has combined the operations in 
i. Pounds of Air per Pound of Coal (p. 35), and 
obtains the following formula: 
Pounds of air per pound of coal 

Per cent carbon in coal 
= 2.31- 



Per cent C02+per cent CO' 

Similarly, Per cent heat lost 

_Per cent carbon in coal 200+per cent CO2 

Heating value of coal ' Per cent CC^+per cent CO 
Xrise in temperature in ° C.X0.2864. 

The values found by this equation are 0.5 per cent low, 
as no cognizance has been taken of the water vapor. 

In rapid work the following formula will be found 
more applicable: Let and n represent the percent- 
ages of oxygen and nitrogen found in the chimney- 
gas; then the ratio of the air actually used to that 
theoretically necessary is expressed by the formula 

21 



1 -,79* 

n 



Applying it in the case of the flue-gas given, it becomes 
21 21 



| 79X74 \ 13-7 
80.2 



= 1.533 ratio. 



Multiplying this by 11.54, the theoretical number of 

* Power, 30, 1121 (1909). 



40 GAS AND FUEL ANALYSIS. 

pounds of air per pound of carbon, we obtain 17.69 as 
against 19.59 on P a ? e 35- 

Multiplying 17.69 by 83 (the per cent of carbon in the 
coal) we obtain 14.15 pounds of air per pound of coal as 
against 15.66 on p. 36. 

Bunte * has given a shorter method for the deter- 
mination of the quantity of heat passing up chimney, 
and one which does not involve the analysis of the 
coal. 

For every per cent of carbonic acid present 43.43 cal. 
per cubic meter of flue-gases have been developed = W\ 
C = specific heat of the flue-gases per cubic meter; 
then W/C represents the initial temperature (which is 
never attained) the ratio of which to the actual exit 
temperature of the flue-gases shows the heat lost. If 
T = this initial temperature and / the rise of tempera- 
ture of the flue-gases, then t/T represents the heat 
lost in the chimney-gases. 

The table on page 41 gives the data for the calcula- 
tion for both pure carbon and coal of average value. 

Applying these data to the problem on page 35 we 
find the initial temperature T to be 1762 C, the rise of 
temperature of the gases was 250 C, the loss is 
250/1762 = 14.2%, against 14.1% found by the calcu- 
lation page 38. 

Bunte also employs a partially graphical method for 
the determination of the loss of heat. In Fig. 12 the 
extreme left-hand column represents the temperatures 
which should be obtained by the combustion of the 
average coal with^ the formation of a chimney-gas con- 

* Jour. f. Gasbeleuchtung, 43, 637 (1900); Abstr. Jour. Soc. Chem. 
Industry, 19, 887. 



L 




PER 



Fig. i2.— Bunte's Chart Showing Heat Lost in Chimn 



ICIENCY 



60 



70 



80 



90 



100 



^^^^^M« 



^>^^^ ^^ 





3500 
2400 
2300 
2200 
2100 
2000 
1900 
1800 
1700 

1600 

o 
1500° 

UJ 

<r 

1400 h 
< 

1300 £' 

2" 

uJ 

1200 H 

_» 

noo 3- 

o 
< 



1000 



900 
800 
700 
600 
500 
40G 
300 
200 
100 



40 30 20 10 

T LOSS 

I3ASES FROM THE CARBONIC ACID AND THE TEMPERATURE. 

[Between pages 40 and 41 ,] 



TABLE XI, 




B B B 

ACTUAL TEMPERATURES 



CALCULATIONS. 



41 



Per Cent of 


Specific Heat 

of 
Chimney Gas. 


Initial Temperature, W/C. 


Degrees C 


CO2 in 
Chimney Gas. 


For Carbon 
= T. 


For Coal 

= r. 


Diff. for 
0.1% C0 2 . 


I 


O.308 


141 


167 


16 


2 


O.310 


280 


331 


16 


3 


O.311 


419 


493 


16 


4 


O.312 


557 


652 


15 


5 


0.3I3 


691 


808 


15 


6 


0.3I4 


830 


961 


15 


7 


0.3I5 


962 


1112 


15 


8 


O.316 


1096 


1261 


15 


9 


O.318 


1229 


1407 


14 


10 


O.319 


1360 


i55o 


14 


11 


O.320 


1490 


1692 


14 


12 


O.322 


1620 


1830 


14 


13 


O.323 


i75o 


1968 


13 


14 


O.324 


1880 


2102 


13 


IS 


O.324 


2005 


2237 


13 


16 


0.325 


2130 


2366 





taining the percentages of carbon dioxide in the column 
next it. Applying this to our case we find the theoretical 
temperature for 11.5% CO, to be 1558°; dividing the 
rise of temperature actually observed — 250 — by this, 
we obtain 16.05%, or 2 % more than by the method 
of page 38. 

Almost the identical result can be obtained from 
Fig. 13 directly: if the point of intersection of the 
diagonal representing the per cent of carbon dioxide 
with the horizontal line denoting the actual tempera- 
ture, on the right, be followed to the bottom of the 
table the per cent of loss is ascertained. 

Fig. 13 is the lower right-hand corner of Fig. 12 
enlarged. 



42 



GAS AND FUEL ANALYSIS. 



ACTUAL TEMPERATURE C. 




ACTUAL TEMPERATURE C. 



Fig. 13.— Bunte's Flue Gas Chart, Enlarged, 



CALCULATIONS. 43 

W. A. Noyes * states that the following formula 
gives close results and is also independent of the com- 
position of the coal. 

07 r^f^ 

Percentage loss = (0.01 1 H qtt^ -0.00605) (tf — t) . 

Lunge f has also given a shorter method for the cal- 
culation of the heat lost. 

The following table % shows roughly the excess of air 
and the per cent of heat lost in the chimney gases: 

PER CENT OF CARBONIC ACID. 

2 3 4 5 6 7 8 9 IO II 12 13 14 15 

VOLUME OF AIR MORE THAN THEORY. 

(Theory =1.0). 

9-5 6 -3 4-7 3- 8 3- 2 2 -7 2 -4 2.1 1.9 1.7 1.6 1.5 1.4 1.3 

PER CENT LOSS OF HEAT. 
.Temp, of chimney gases, 51 8° F 

90 60 45 36 30 26 23 20 18 16 15 14 13 12 

Notes. — The increase in per cent of nitrogen over that 
in the air, 79.1, is due to the condensation of the steam 
formed from the hydrogen in the coal: this, as has been 
shown, p. 34, amounts to 1.4 of the 20.9 volumes of 
oxygen, and form 2.8 volumes or mois of water. 

The question is often asked " What percentage of 
carbon dioxide should be obtained?" The table by 

* Am. Chem. Journal, 19, 162 

t Zeit. f. angewandte Chemie, 1889, 240. 

t Arndt's Econometer Circular. 



44 



GAS AND FUEL ANALYSIS. 





\ 




































\ 


i 














MAXIMUM AVAILABLE 

C0 2 PERCENTAGE WITH THEORETICALLY 

PERFECT COMBUSTION 

Solid Fuels 

Wood 20.0-20.9 
Lignite 19.5-20.5 
Anthracite 19.0-20.5 
Bituminous 18.5-20.5 

Liquid Fuel 

Fuel Oil 14.0-16.5 

Gaseous Fuels 

Blast Furnace 19.2 Average 
Producer 15.0 " 
Natural 8.5-11.5 
Coke Oven 4.5 Average 








\ 




















V 

\ 




















\ 


L 




















\ 




















\ 




















\ 






















































































































a 


































01=0, 




































+ 


































« a 

O * 

© 

+ B 
H o 

fl 

© <; 
+ 

— a 

© a 

~ - 






































































































































































































































































































































































































































































CO " 


f U 


5 *. 


3 c- 


- a 


3 C 


1 < 


5 I- 


H C 


1 o* 


) «d 


A If 


3 « 


3 r- 


a 


3 C 


> <z 


> O 









tn 


(M 


O 




T> 


t* 


43 















C 


tf) 






*■* 


3 






GO 

CO 


o 




,fl 




f ) 






CO 


a 


H 


E 


^ 


d 







CO 


bl) 


-(-> 




O 


u 


fl 


CO 


H3 


OQ 


.5 

a 


o 

CO 


a 


w 


o 
u 




IH 


N 


-M 


GO 


O 

4^ 


f 


o 




-a 


1 


»-■ 


o 


bD 


Tt" 


0, 




,° 


H 


>l 


~+l 


£ 





*3 


N 


>> 

£ 


£ 


0) 


<N 


0> 




J-. 




5 









nfl 




<u 




*3 




ja 


G J 


fl 




+■» 




o 




-t-J 


QQ 


o 




rt 




Fh 






50 


P-i 




O 
O 

0) 

cd 



fl 
o 



aSTnuooJOd; s qq ranraixnj^ 



CALCULATIONS 4$ 

Azbe,* Fig. 14, shows the available CO2 with different 
fuels. With coal, the maximum efficiency is between 
14 and 15.5 per cent; an average of from 12 to 14 per 
cent; with oil, 13 to 14 per cent; with natural gas from 
8 to 9 per cent, are all good practice, f Carbon mon- 
oxide should not exceed 0.5 per cent. 

If the per cent of oxygen be 1.5 — 2 (and the draft 
through the fire high), the fire is too thick; if it be less 
than 8 per cent the fire is too thin. 

The permissible excess of air is with coal from 30-100 
per cent; with oil not over 25 per cent; and with 
natural gas 10 or 15 per cent. 

In attempting to obtain good combustion, there is 
danger in carrying it too far, i.e., in forcing the per- 
centage of CO2 too high, ensuring a loss, through the 
formation of carbon monoxide. Care should be taken 
that the gain in carbon dioxide be not more than offset 
by a loss in carbon monoxide. 

Determination of Loss Due to Formation of Car- 
bonic Oxide. — A. From page ^^, seventh column, we see 
that 10.8 grams carbon of that in 186. 1 grams of coal 
burn to carbon monoxide; this is 58 grams carbon per 
kilo as in B. 

B. On page 36 we see that 58 grams of carbon burned 
to carbonic oxide; for every gram of carbon burned to 
carbonic oxide there is a loss of 5.66 C, in this case a 
loss of 328 C. The heating value of the coal is 7220 C, 
hence the loss is 4.5 per cent. Combustion gases from oil 
gas fuels should always be tested for carbon monoxide. J 

* Azbe, Power, 43, 543 (1916). 

t Power, 48, 956 (1918). 

t Wales, Power, 45, 347 (1917). 



46 



OAS AND FUEL ANALYSIS. 




Fig. 15.— Losses in an Average Industrial Plant having 1000-2000 
H.P. The Branches Turning to the Left Represent the 

Losses. 



CALCULATIONS. 47 

Other Losses. — Kreisinger and Ovitz (Bureau Mines 
Bulletin 97, p. 35), have admirably shown the other 
sources of loss. This is so important that it is here repro- 
duced, Fig. 14. 

References. — Hutzel, Power, 44, 821 (1916). 
O'Neill, Power, 47, 52 (1918). • 

J. W. Richards, " Metallurgical Calculations" 



CHAPTER V. 

APPARATUS FOR THE ANALYSIS OF FUEL AND 
ILLUMINATING GASES. 

Hempel's Apparatus. 

Description. — The apparatus, Figs. 16 and 17, is 
very similar in principle to that of Orsat; the burette 
is longer, admitting of the reading of small quantities 
of gas, and the pipettes are separate and mounted in 
brass clamps on iron stands. P shows a " simple' ' 
pipette* provided with a rubber bag; this form, after 
ten years of use, can be said to satisfactorily take the 
place of the cumbersome ''compound " pipette. 

The pipette for fuming sulphuric acid f is shown at 
F, and differs from the ordinary in that vertical tubes 
after the manner of those in the Orsat pipettes replace 
the usual glass beads. This prevents the trapping of 
any gas by the filling, which was so common with the 
beads and glass wool. E represents the large explo- 
sion pipette,;}; of about 250 cc. capacity, with walls half 
an inch thick ; the explosion wires enter at the top and 
bottom to prevent short-circuiting; mercury is the 
confining liquid. The small explosion pipette holds 

* Gill, Am. Chem. J., 14, 231 (1892). 
\ Id., J. Am. Chem. Soc, 18, 67 (1896). 
% Gill, J. Am. Chem. Soc, 17, 771 (1895). 

48 



APPARATUS. 



49 



about no cc. and is of glass, the same thickness as 
the simple pipettes. Water is here used as the confin- 
ing liquid, and also usually in the burette. 

An induction coil capable of giving a half-inch spark, 




Fig. 16. — Showing Hempel Burette connected with the 
Simple Pipette on the Stand. 



with a six-cell "Samson" battery, four "simple" 
pipettes and a mercury burette, complete the outfit. 

The burette should be carefully calibrated and the 
corrections may very well be etched upon it opposite 
the io-cc. divisions. 



5o 



GAS AND FUEL ANALYSIS. 



In working with the apparatus the pipettes are placed 
upon the adjustable stand 5 and connection made with 
the doubly bent capillary tube. 

Manipulation. — To acquire facility with the use of 
the apparatus before proceeding to the analysis of 




Fig. 17. — Explosion Pipette for Mercury and Sulphuric 
Acid Pipette. 



illuminating-gas, it is well to make the following deter- 
minations, obtaining " check readings " in every case: 
I. Oxygen in air, by (1) absorption with phosphorus; 

(2) absorption with potassium (or sodium) pyrogallate; 

(3) by explosion with hydrogen. 



APPARATUS. 51 

I. DETERMINATION OF OXYGEN IN AIR. 

(i) By Phosphorus. — 100 cc. of air are measured 
out as with the Orsat apparatus, the burette being 
allowed to drain two minutes. The rubber connectors 
upon the burette and pipette are filled with water, the 
capillary tube inserted, as far as it will go, by a twist- 
ing motion, into the connector upon the burette, thus 
filling the capillary with water; the free end of the 
capillary is inserted into the pipette connector, the 
latter pinched so as to form a channel for the water 
contained in it to escape, and the capillary twisted and 
forced down to the pinch-cock. There should be as 
little free space as possible between the capillaries and 
the pinch-cock. Before using a pipette, its connector 
(and rubber bag) should be carefully examined for 
leaks, especially in the former, and if any found the 
faulty piece replaced. 

The pinch-cocks on the burette and pipette are now 
opened, the air forced over into the phosphorus, and 
the pinch-cock on the pipette closed ; action im- 
mediately ensues, shown by the white fumes; after 
allowing it to stand for fifteen minutes the residue is 
drawn back into the burette, the latter allowed to drain 
and the reading taken. The absorption goes on best 
at 20° C, not at all at below 15 C. ; it is very much 
retarded by small amounts of ethene and ammonia. 
No cognizance need be taken of the fog of oxides of 
phosphorus. 

(2) By Pyrogallate of Potassium. — 100 cc. of air 
are measured out as before, the carbon dioxide absorbed 
with potassium hydrate and the oxygen with potassium 



S 2 GAS AND FUEL ANALYSIS. 

pyrogallate, as with the Orsat apparatus ; before setting 
aside the pyrogallate pipette, the number of cubic 
centimeters of oxygen absorbed should be noted upon 
the slate s on the stand. This must never be omitted 
with any pipette save possibly that for potassium 
hydrate, as failure to do this may result in the ruin of 
an important analysis. The reason for the omission in 
this case is found in the large absorption capacity — four 
to five litres of carbon dioxide — of the reagent. 

(3) By Explosion with Hydrogen. — 43 cc. of air 
and 57 cc. of hydrogen are measured out, passed into 
the small explosion pipette, the capillary of the pipette 
filled with water, the pinch-cocks and glass stop-cock 
all closed, a heavy glass or fine wire gauze screen 
placed between the pipette and the operator, the spark 
passed between the spark wires, and the contraction 
in volume noted. The screen should never be omitted, 
as serious accidents may occur thereby. The oxygen is 
represented by one third of the contraction. For very 
accurate work the sum of the combustible gases should 
be but one sixth that of the non-combustible gases, 
otherwise some nitrogen will burn and high results will 
be obtained ; * that is, (H + O) : (N + H) : : 1 : 6. 

II. ANALYSIS OF ILLUMINATING-GAS. 

100 cc. of gas are measured from the bottle contain- 
ing the sample into the burette. 

Determination of Carbon Dioxide. — The burette 
is connected with the pipette containing potassium 

* This is shown in the work of Gill and Hunt, J. Am. Chem. 
Soc, 17, 9S7 (1895). 



APPARATUS. S3 

hydrate and the gas passed into it with shaking until 
no further diminution in volume takes place. 

Uluminants, C w H 9lt , C M H 2n _ 6 Series. — The rubber 
connectors are carefully dried out with filter-paper, a 
dry capillary used, and the gas passed into the pipette 
containing fuming sulphuric acid and allowed to stand, 
with occasional passes to and fro, for forty-five minutes. 
On account of the extremely corrosive nature of the 
absorbent it is not advisable to shake the pipette, as 
in case of breakage a serious accident might occur. 
For Boston gas this is sufficient, although with richer 
gases check readings to 0.2 cc. should be obtained. 
It is then passed into potassium hydrate, as in the 
previous determination, to remove any sulphurous acid 
which may have been formed and any sulphuric 
anhydride vapor, these having a higher vapor tension 
than water. The difference between this last reading 
and that after the absorption of the carbon dioxide 
represents the volume of " illuminants " or " heavy 
hydrocarbons ' ' present. 

As has already been stated, page 25, saturated bromine 
water may replace the fuming sulphuric acid. Fuming 
nitric acid is not recommended, as it is liable to oxidize 
carbonic oxide. 

Oxygen. — This is absorbed, as in the analysis of 
air, by potassium or sodium pyrogallate. 

Carbonic Oxide. — The gas is now passed into am- 
moniacal cuprous chloride, until the reading is constant 
to 0.2 cc. ; it is then passed into a second pipette,* 
which is fresh, and absorption continued until constant 
readings are obtained. 

* White states this should not have absorbed more than 10 cc. 



54 GAS AND FUEL ANALYSIS. 

For very accurate work the gas should be absorbed in 
a U tube of iodic anhydride heated to 150 . Extreme 
care must be taken to prevent contact of the gas with 
sulphur, organic matter, as vaseline and rubber,* as the 
anhydride is readily reduced. The reaction is 

5CO + I 2 5 = 5C0 2 + 2l. 

The diminution in volume represents the carbonic oxide; 
or the iodine can be determined in the usual way with 
thiosulphate. 

The volume of air contained in the tube should be 
corrected for as follows: One end of the tube is plugged 
tightly and the other end connected with the gas burette 
partly filled with air. A bath of water at 9 C. is placed 
around the U-tube and the reading of the air in the gas 
burette recorded when constant; the bath is now heated 
to ico° and the burette reading again recorded when 
constant. The increase in reading represents one third 
the volume of the U-tube, 273 1273 + (100— 9): 13:4. 

Methane and Hydrogen. — (a) Hinman y s Method.^ 
— The gas left from the absorption of carbonic oxide 
is passed into the large explosion pipette. About half 
the requisite quantity of oxygen (40 cc.) necessary 
to burn the gas is now added, mercury introduced 
through the T in the connector sufficient to seal the 
capillary of the explosion pipette, all rubber connectors 
carefully wired, the pinch-cocks closed, and the pipette 
cautiously shaken. A screen of heavy glass or fine 
wire gauze is interposed between the operator and the 

* Morgan & McWhorter, J. Am. Chem. Soc, 22, 14 (1900). 
t Gill and Hunt, J. Am. Chem. Soc, 17, 987 (1895). 



APPARATUS. 55 

apparatus, the explosion wires are connected with the 
induction coil, a spark passed between them and the 
pinch-cocks opened, sucking in the remainder of the 
oxygen. The capillary is again sealed with mercury, 
the stop-cock opened and closed, to bring the contents 
of the pipette to atmospheric pressure, and the explo- 
sion repeated as before, and the stop-cock opened. 

It may be found expedient, to increase the inflamma- 
bility of the mixture, to introduce 5 cc. of " detonating- 
gas," the hydrolytic mixture of hydrogen and oxygen. 
The gas in the pipette containing carbon dioxide, 
oxygen, and nitrogen is transferred to the mercury 
burette and accurately measured. The carbon dioxide 
resulting from the combustion of the marsh-gas is 
determined by absorption in potassium hydrate ; to 
show the presence of an excess of oxygen, the amount 
remaining is determined by absorption with potassium 
pyrogallate. 

The calculation is given on page 56. For very 
accurate work a second analysis should be made, 
making successive explosions, using the percentages of 
methane and hydrogen just found as a basis upon which 
to calculate the quantity of oxygen to be added each 
time. The explosive mixture should be so proportioned 
that the ratio of combustible gas (i.e., CH 4 , H and O) 
is to the gases which do not burn (i.e., N and the 
excess of CH 4 and H) as 100 is to about 50 (from 26 
to 64);* otherwise the heat developed is so great as 
to produce oxides of nitrogen, which, being absorbed 

* Bunsen, Gasometrische Methoden, 2d ed., p. 73 (1S77). 



56 GAS AND FUEL ANALYSIS. 

in the potassium hydrate, would affect the determina* 
tion of both the methane and the hydrogen. The 
oxygen should preferably be pure, although commer- 
cial oxygen, the purity of which is known, can be 
used ; the oxygen content of the latter should be tested 
from time to time, especially with different samples. 

{p) HempcV s Method* — From 12 to 15 cc. of the 
gas are measured off into the burette (e.g., 13.2 cc.) 
and the residue is passed into the cuprous chloride 
pipette for safe keeping. That in the burette is now 
passed into the small explosion pipette; a volume of 
air more than sufficient to burn the gas, usually about 
85 cc, is accurately measured and also passed into the 
explosion pipette, and in so doing water from the 
burette is allowed to partially fill the capillary of the 
pipette and act as a seal. The rubber connectors upon 
the capillaries of the burette and pipette are carefully 
wired on, both pinch-cocks shut, and the stop-cock 
closed. The pipette is cautiously shaken, the screen 
interposed, the explosion wires connected with the 
induction coil, a spark passed between them, and the 
stop-cock immediately opened. The gas in the pipette, 
containing carbon dioxide, oxygen, and nitrogen, is 
transferred to the burette, accurately measured, by 
reading immediately, to prevent the absorption of car- 
bon dioxide, and carbon dioxide and oxygen deter- 
mined in the usual way. 

Calculation. — (a) Hinman's Method. — 56.2 cc. of 
gas remained after the absorptions; 77.4 cc. of oxygen 
were introduced, giving a total volume of 133.6 cc. 



* Hempel, Gas Analytische Methoden, 3d ed., p. 245 (1901). 



APPARA TUS. 



57 



Residue after explosion 46.9 cc. 

Residue after C0 2 absorption 28.2 " 

Carbon dioxide formed 18.7 " 

Contraction 133.6 — 46.9=: 86.7 " 

Residue after O absorption 25.6 " 

Oxygen in excess, 28.2 — 25.6 = 2.6 " 

The explosion of marsh-gas or methane is repre- 
sented by the equation* 



CH, 



+ 



O. 



o. 



CO, 



+ 



HO 



+ 



HO 



From this it is evident that the volume of carbon 
dioxide is equal to the volume of methane present; 
therefore in the above example, in the 56.2 cc. of gas 
burned there were 18.7 cc. methane. 

The total contraction is due (1) to the disappearance 
of oxygen in combining with the hydrogen of the 
methane, and (2) to the union of the free hydrogen 
with oxygen. The volume of the methane having 
been found, (1) can be ascertained from the equation 
above, equals twice the volume of the methane; hence 

86.7 - (2 X 18.7) = 49-3 cc, 

contraction which is due to the combustion of hydrogen. 
This takes place according to the following reaction : * 



H, 


+ 


H, 


+ O, = 


H.O + 


H 3 



* H 2 being as steam at ioo° C. At ordinary temperatures 
this is condensed, giving rise to " total contraction." 



58 



GAS AND FUEL ANALYSIS. 



Hydrogen then requires for its combustion half its 
volume of oxygen, hence this 49.3 cc. represents a 
volume of hydrogen with \ its volume of oxygen, or 
| volumes; hence the volume of hydrogen is 32.9 cc. 

(b) HempeVs Method. — Of the 82 cc. of gas remain- 
ing after the absorptions, 13.2 cc. were used for the 
explosion ; 86.4 cc. air introduced giving a total volume 
of 99.6 cc. 

Residue after explosion 78.0 cc. 

Residue after CO a absorption. 73 .2 



Carbon dioxide formed 4.8 

Contraction 99-6 — 78.0 ~ 21 .6 

Residue after O absorption 70.2 

Oxygen in excess. .73.2 — 70.2 = 3.0 



The carbon dioxide being equal to the methane 
present, in the 13.2 cc. of gas burned, there were 
4.8 cc. of methane. The volume of methane is found 
by the proportion 13.2 : 82 : : 4.8 : x, whence x — 
29.8 cc. 

The hydrogen is calculated similarly. 

The following method of calculation may be substi- 
tuted for that on page 55: Let m = methane, h = 
hydrogen, c = total contraction, and O = oxygen 
actually used ; then 



and 



2m -| — = 
' 2 



, 3 h 
2m + — = c, 



APPARA TUS. 




30- c 


m i— 


4 


h = 


c - 0. 



59 

whence 



and 



The explosion can also be made after the absorption 
of oxygen and thus the troublesome absorption of car- 
bonic oxide avoided. The calculation is then, if C = 
carbonic oxide, K = CO a formed : 

C 3I1 

fc = -4-2111+— , . . . . (I) 

K = C + m, (2) 

V = C + m + h; .... (3) 
whence 

h = V - K, 

3 ^ 3 

2K 2C 

m = V -A . 

3 ■ 3 

Another method for the estimation of hydrogen is 
by absorption with palladium sponge ; * it, however, 
must be carefully prepared, and it is the author's 
experience that one cannot be sure of its efficacy when 
it is desired to make use of it. A still better absorbent 
of hydrogen f is a 1 per cent solution of palladous 

* Hempel, Berichte deutsch. ch. Gesell., 12, 636 and 1006(1879). 
f Campbell and Hart, Am. Chem. J., 18, 294 (1896). 



60 GAS AND FUEL ANALYSIS. 

chloride at 50 C. ; when fresh this will absorb 20-50 
cc. of hydrogen in ninety minutes. A proportionately 
longer time is required if more hydrogen be present or 
the solution nearly saturated. The methane could 
then be determined by explosion or by mixing with 
air and passing to and fro over a white-hot platinum 
spiral in a tubulated pipette called the grisoumeter * 
(grisou = methane). 

Nitrogen. — There being no direct and convenient 
method for its estimation with this apparatus, the per- 
centage is obtained by finding the difference between 
the sum of all the percentages of the gases determined 
and 100 per cent. 

New f determines nitrogen in illuminating-gas di- 
rectly after the method of Dumas in organic sub- 
stances; 150 cc. of gas are used, the hydrocarbons 
partially absorbed by fuming sulphuric acid and the 
remainder burned in a combustion tube with copper 
oxide ; the carbon dioxide is absorbed and the residual 
nitrogen collected and measured. 

Accuracy and Time Required. — For the absorp- 
tions the apparatus is accurate to o. I cc. ; for explosions 
by Hinman's method % the methane can be determined 
within 0.2 per cent, the hydrogen within 0.3 per cent; 
by Hempel's method within 1 per cent for the methane 
and 7.5 per cent for the hydrogen. The time required 
for the analysis of illuminating-gas is from three to 
three and one-half hours; for air, from fifteen to twenty 
minutes. 

* Winkler, Fres. Zeit., 28, 269 and 288. 
f J. Soc. Chem. Ind., II, 415 (1892). 
% Gill and Hunt, loc cit. 



APPARA TUS. 6l 

Notes. — The object in filling the capillaries of the 
explosion pipettes with water or mercury before the 
explosion is to prevent the bursting of the rubber con- 
nectors on them. With mercury this is effected by 
introducing it through the T joint in the connector. 
After testing for oxygen with the pyrogallate a small 
quantity of dilute acetic acid is sucked into the burette 
to neutralize any alkali which by any chance may have 
been sucked over into it. The acid is rinsed out with 
water and this forced out by mercury before the burette 
is used again. 

The water in the burette should be saturated with 
the gas which is to be analyzed— as illuminating-gas 
— before beginning an analysis. The reagents in the 
pipettes should also be saturated with the gases for 
which they are not the reagent. For example, the 
fuming sulphuric acid should be saturated with oxygen, 
carbon monoxide, methane, hydrogen, and nitrogen; 
this is effected by making a blank analysis using 
illuminating-gas . 

The method of analysis of the residue after the 
absorptions have been made by explosion is open to 
two objections: 1st, the danger of burning nitrogen by 
the violence of the explosion; and 2d, the danger of 
breakage of the apparatus and possible injury to the 
operator. These may be obviated by employing the 
apparatus of Dennis and Hopkins,* which is practically 
a grisoumeter with mercury as the confining liquid ; or 
that of Jager, t who burns the gases with oxygen in a 

* J. Am. Chem. Soc, 21, 398 (1899). 

f J. f. Gasbeleuchtung, 41, 764. Abstr. J. Soc. Chem. Ind., 
17, 1190 (1898). 



62 GAS AND FUEL ANALYSIS. 

hard-glass tube filled with copper oxide. By heating 
to 25c C. nothing but hydrogen is burned; higher 
heating of the residue burns the methane. Or the mix- 
ture of oxygen and combustible gases, bearing in mind 
the ratio mentioned at the bottom of page 55; can be 
passed to and fro through Drehschmidt's * capillary 
heated to bright redness. This consists of a platinum 
tube 20 cm. long, 2 mm. thick, 1.7 mm. bore, filled with 
three platinum or palladium wires. The ends of the tube 
are soldered to capillary brass tubes and arranged so 
that these can be water cooled. It is inserted between 
the burette and a simple pipette, mercury being the con- 
fining liquid in both cases. The air contained in the 
tube can be determined as in the case of the tube contain- 
ing iodic anhydride, p. 54. 

To the method of explosion by the mixture of an 
aliquot part of the residue with air, method (b), there 
is the objection that the carbon dioxide formed is meas- 
ured over water in a moist burette, giving abundant 
opportunities for its absorption, and that the errors in 
anylysis are multiplied by about six, in the example 

820 
T3^« 



by 8 



References. — 

Dennis, " Gas Analysis." 

White, " Technical Gas and Fuel Analysis" 

* Ber. d. deut. chem. Gesell., 21, 3242 (1888). 



CHAPTER VI. 

REAGENTS AND ARRANGEMENT OF THE 
LABORATORY. 

THE reagents used in gas-analysis are comparatively 
few and easily prepared. 

Hydrochloric Acid, Sp. gr. i.io. — Dilute "muri- 
atic acid " with an equal volume of water. In addi- 
tion to its use for preparing cuprous chloride, it finds 
employment in neutralizing the caustic solutions which 
are unavoidably more or less spilled during their use. 

Fuming Sulphuric Acid. — Saturate " Nordhausen 
oil of vitriol," with sulphuric anhydride. Ordinary 
sulphuric acid may be used instead of the Nordhausen ; 
in this case about an equal weight of sulphuric an- 
hydride will be necessary. Absorption capacity \ I cc. 
absorbs 8 cc. of ethene (ethylene). 

Acid Cuprous Chloride. — The directions given in 
the various text-books being troublesome to execute, 
the following method, which is simpler, has been 
found to give equally good results. Cover the bottom 
of a two-liter bottle with a layer of copper oxide or 
14 scale f in. deep, place in the bottle a number of 
pieces of rather stout copper wire reaching from top 
to bottom, sufficient to make a bundle an inch in 
diameter, and fill the bottle with common hydrochloric 

63 



64 GAS AND FUEL ANALYSIS. 

acid of 1. 10 sp. gr. The bottle is occasionally shaken, 
and when the solution is colorless, or nearly so, it is 
poured into the half-liter reagent bottles, containing 
copper wire, ready for use. The space left in the 
stock bottle should be immediately filled with hydro- 
chloric acid (i.io sp. gr.). 

By thus adding acid or copper wire and copper 
oxide when either is exhausted, a constant supply of 
this reagent may be kept on hand. 

The absorption capacity of the reagent per cc. is, 
according to Winkler, 15 cc. CO; according to 
Hempel 4 cc. The author's experience with Orsat's 
apparatus gave 1 cc. 

Care should be taken that the copper wire does not 
become entirely dissolved and that it extend from the 
top to the bottom of the bottle; furthermore the 
stopper should be kept thoroughly greased the more 
effectually to keep out the air, which turns the solution 
brown and weakens it. 

Ammoniacal Cuprous Chloride. — The acid cu- 
prous chloride is treated with ammonia until a faint 
odor of ammonia is perceptible; copper wire should 
be kept in it similarly to the acid solution. This 
alkaline solution has the advantage that it can be 
used when traces of hydrochloric acid vapors might 
be harmful to the subsequent determinations, as, for 
example, in the determination of hydrogen by absorp- 
tion with palladium. It has the further advantage 
of not soiling mercury as does the acid reagent. 

Absorption capacity, 1 cc. absorbs 1 cc. CO. 

Cuprous chloride is at best a poor reagent for the 
absorption of carbonic oxide; to obtain the greatest 






REAGENTS AND LABORATORY. 65 

accuracy where the reagent has been much used, the 
gas should be passed into a fresh pipette for final 
absorption, and the operation continued until two 
consecutive readings agree exactly. The compound 
formed by the absorption — possibly Cu Q COCl a — is very 
unstable, as carbonic oxide may be freed from the 
solution by boiling or placing it in vacuo; even if it 
be shaken up with N 2 , the gas is given off, as shown 
by the increase in volume and subsequent diminution 
when shaken with fresh cuprous chloride. 

Hydrogen. — A simple and effective hydrogen gen- 
erator can be made by joining two six-inch calcium 
chloride jars by their tubulatures. Pure zinc is filled 
in as far as the constriction in one, and the mouth 
closed with a rubber stopper carrying a capillary tube 
and a pinch-cock. The other jar is filled with 
sulphuric acid I : 5 which has been boiled and cooled 
out of access of air. The mouth of this jar is closed 
with a rubber stopper carrying one of the rubber bags 
used on the simple pipettes. 

Mercury. — The mercury used in gas analysis should 
be of sufficient purity as not to " drag a tail" when 
poured out from a clean vessel. It may perhaps be 
most conveniently cleaned by the method of J. M. 
Crafts, which consists in drawing a moderate stream 
of air through the mercury contained in a tube about 
3 feet long and \\ inches internal diameter. The tube 
is supported in a mercury-tight V-shaped trough, of 
size sufficient to contain the metal if the tube breaks, 
one end being about 3 inches higher than the other. 
Forty-eight hours* passage of air is sufficient to purify 
any ordinary amalgam. The mercury may very well 



66 GAS AND FUEL ANALYSIS, 

be kept in a large separatory funnel under a layer of 
strong sulphuric acid. 

Pallado us Chloride. — 5 grams palladium wire are dis- 
solved in a mixture of 30 cc. hydrochloric and 2 cc. nitric 
acid, this evaporated just to dryness on a water-bath, re- 
dissolved in 5 cc. hydrochloric acid and 2 5 cc. water, and 
warmed until solution is complete. It is diluted to 750 cc. 
and contains about one per cent of palladous chloride. It 
will absorb about two thirds of its volume of hydrogen. 

Phosphorus. — Use the ordinary white phosphorus 
cast in sticks of a size suitable to pass through the 
opening of the tubulated pipette. 

Potassium Hydrate. — (a) For carbon dioxide de- 
termination, 500 grams of the commercial hydrate is 
dissolved in 1 liter of water. 

Absorption capacity, 1 cc. absorbs 40 cc, C0 2 . 

(b) For the preparation of potassium pyrogallate 
for special work, 120 grams of the commercial hydrate 
is dissolved in 100 cc. of water. 

Potassium Pyrogallate. — Except for use with the 
Orsat or Hempel apparatus, this solution should be 
prepared only when wanted. The most convenient 
method is to weigh out 5 grams of the solid acid upon 
a paper, pour it into a funnel inserted in the reagent 
bottle, and pour upon it 100 cc. of potassium hydrate 
(a) or (b). The acid dissolves at once, and the solution 
is ready for use. 

If the percentage of oxygen in the mixture does 
not exceed 28, solution (a) may be used;* if this 
amount be exceeded, (b) must be employed. Other- 

* Clowes, Jour. Soc. Chem. Industry, 15, 170. Anderson, J. I. and 
Eng. Chem., 7, 595 (1915), recommends a solution of 15 grm. pyrogaliol 
in 100 cc. KOII sp. gr. 1.55. 



REAGENTS AND LABORATORY, 67 

wise carbonic oxide may be given off even to the extent 
of 6 per cent. 

Attention is called to the fact that the use of potassium 
hydrate purified by alcohol has given rise to erroneous 
results. 

Absorption capacity, 1 cc. absorbs 2 cc. O. 

Sodium Hydrate. — Dissolve the commercial hydrate 
in three times its weight of water. This may be employed 
in all cases where solution (a) of potassium hydrate is 
used. The chief advantage in its use is its cheapness. 
Anderson * states that it is not practicable to use it for 
pyrogallol; this is at variance with the experiments of 
Wehl f , Berthelot J and the author. It has been so 
used in the author's laboratory for more than twenty- 
five years, the absorption is rapid and complete. Sodium 
pyrogallate is, however, a trifle slower in action than the 
corresponding potassium salt. 

ARRANGEMENT OF THE LABORATORY. 

The room selected for a laboratory for gas-analysis 
should be well lighted, preferably from the north and 
east. To prevent changes in temperature it should 
be provided with double windows, and the method of 
heating should be that which will give as equable a 
temperature as possible. In the author's laboratory, 
instead of the usual tables, shelves are used, 18 inches 
wide and ij inches thick, best of slate or soapstone, 
firmly fastened to the walls, 30 inches from tHe floor; 
the Orsat apparatus, when not in use, may be sus- 
pended from these. The reagents are contained in 

* Loc. cit. f Ber. 14, 2659 (1881). 

t Ann. chim. phys., 15, 294 (i£ 



63 



GAS AND FUEL ANALYSIS. 



half liter bottles fitted with rubber stoppers, placed 
upcn a central table convenient to all. Here are 
found scales, funnels and graduates for use in mak- 
ing up reagents. Tap water is piped around to each 
place by |-inch tin pipe and T \-inch rubber tubing 
from a J-inch "main/ 1 being supplied at the tem- 




Fig. 18 — Muencke's Aspirator. 

perature of the room from bottles placed about six 
feet above the laboratory shelves. A supply of a 
gallon per day per student should be provided. 

At the right of each place is fixed a sand-glass of 
cylindrical rather than conical form, graduated to 
minutes for the draining of the burettes. The "egg- 
timers " found in kitchen-furnishing stores serve the 
purpose admirably. 




REAGENTS AND LABORATORY. 69 

" Unknown gases'* for analysis are best contained 
in a Muencke double aspirator, Fig. 18, where they 
can be thoroughly mixed before distribution and con- 
veyed by a pipe to the central table. 

Finally, the laboratory should contain a stone-ware 
sink provided with an efficient trap of the same 
material, to prevent mercury from being carried into 
and corroding the lead waste-pipes. 

Drawers should be provided with compartments for 
various sizes of rubber connectors, pinchcocks, glass 
tubing, stoppers and fittings, and tools. When work- 
ing with the Orsat apparatus alone, three feet of shelf 
space may be allowed to each student; when using this 
with another, as, for example, the Bunte, another 
foot shouFd be added. 

The course which the writer has been in the habit 
of giving to the Mechanical and Electrical Engineers 
embraces two exercises in the laboratory of two hours 
each, supplemented with six hours of lectures. The 
students in the laboratory make an analysis of air and 
an "unknown" furnace-gas, take and analyze an 
actual sample of chimney-gas, and make the calcula- 
tion of heat lost and air used. In the lectures, the 
subject of gas-analysis and its other applications, and 
of fuels, their origin, description, preparation, appli- 
cation, analysis, and determination of heating value, 
are described. 



CHAPTER VII. 

FUELS— SOLID, LIQUID, AND GASEOUS: THEIR 
DERIVATION AND COMPOSITION. 

The substances employed as fuels are: 

a. Solid Fuels. — Wood, peat, brown, bituminous 
and anthracite coal, charcoal, coke, and oftentimes 
various waste products, as sawdust, bagasse, straw, 
and spent tan. 

b. Liquid Fuels. — Crude petroleum and various 
tarry residues. 

c. GASEOUS FUELS. — Natural gas, producer, blast- 
furnace, water, and illuminating gas. 

The essential constituents in all these are carbon and 
hydrogen; the accessory, oxygen, nitrogen, and ash; 
and the deleterious, water, sulphur, and phosphorus. 

a. Solid Fuels. 

Wood is composed of three substances — cellulose, 
or woody fibre (C 6 H ]0 O 6 ) w ; the components of the sap, 
the chief of which is lignine, a resinous substance of 
identical formula with cellulose; and water. The 
formation of cellulose from carbon dioxide and water 
may be represented by the equation 

6CO,+ 5 H 2 O = C 6 H 10 O 6 + 6O,. 

The amount of water which wood contains determines 
its value as a fuel. This varies from 29 per cent in ash 

70 



FUELS—SOLID, LIQUID, AND GASEOUS. 71 

to 50 per cent in poplar; it varies also with the season 
at which the wood is cut, being least when the sap is in 
the roots — in December and January. This difference 
may amount to 10 per cent in the same kind of wood. 

The harder varieties of wood make the best fuel, a 
cord of seasoned hardwood being about equal to a ton 
of coal. Yellow pine, however, has but half this 
value; the usual allowance in a boiler-test is 0.4 the 
value of an equal weight of coal. 

The ash of wood is mainly potassium carbonate, 
with traces of other commonly occurring substances, 
as lime, magnesia, iron, silica, and phosphoric acid. 

The percentage composition of wood may be con- 
sidered as approximately, 

Water, Carbon. Hydrogen. Oxygen. Ash. Sp. Gr. 

20 39 4.4 35.6 I 0.5.* 

When burned it yields about 4000 C. per kilo, and 
requires 6 times its weight of air or 4.6 cu. m. (74.1 
cu. ft. per pound) for its combustion. 

Peat finds considerable application in Europe, and 
is coming into use in this country in the form of bri- 
quettes. To this end it is reduced to a dry powder 
and compressed into small cylindrical blocks; it is 
claimed to be as efficient as coal at half the price. It 
is also proposed to gasify peat after the mannei of 
coal. Peat is produced by the slow decay under water 
of certain swamp plants, more especially the mosses 
(Sphagnaceae), evolving methane (CH 4 ) (marsh-gas) 
and carbon dioxide (C0„). 

It contains considerable moisture, from 20 to 50 
per cent, and 10 per cent even when "thoroughly 

* Mills & Rowan, Fuels, p. II. 



72 GAS AND FUEL ANALYSIS. 

dry." Thirty per cent of its available heat is employed 
in evaporating this moisture. The high content of 
ash, from 3 to 30 per cent, averaging 15 per cent, also 
diminishes its value as a fuel. 

The ash of peat differs from that of wood in contain- 
ing little or no potassium carbonate. 

The percoitage composition of peat may be consid- 
ered as approximately, 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sp. Gr- 

German 16.4 41.0 4.3 23.8 2.6 11.9 1.05 

American... 20.8 40.8 4.4 26.6 7.7 — 

Such peat is about equivalent to wood in its heating 
effect, one pound evaporating from 4.5 to 5 pounds 
of water. 

Coal. — Geologists tell us that coal was probably 
produced by the decay under fresh water of plants 
belonging principally to the Conifer, Fern and Palm 
families; these nourished during the Carboniferous 
Age to an extent which they never approached before 
or since. Representatives of the last family, which 
it is thought produced most of the coal, have been 
found 2 to 4 feet in diameter and 80 feet in height. 

By their decay, carbon dioxide " choke-damp/' 
marsh-gas li fire-damp,' ' and water were evolved. 
The change might be represented by the equation 

6C.H,., O. = 7 CO, + 3 CH, + i 4 H,0 + C,.H M 0,. 

Cellulose. Bituminous Coal. 

Some idea of the density of the vegetation and the 
time required may be obtained from the fact that it 
has been calculated that 100 tons of vegetable matter 
— the amount produced per acre per century — if com- 
pressed to the specific gravity of coal and spread over 



FUELS— SOLID, LIQUID, AND GASEOUS. 73 

an acre would give a layer less than 0.6 of an inch 
thick. Now four fifths of this is lost in the evolution 
of the gaseous products, giving as a result an accumu- 
lation of one eighth of an inch per century, or one foot 
in 10,000 years. * 

Brown Coal or Lignite may be regarded as forming 
the link between wood and coal ; geologically speaking 
it is of later date than the true coal. Most of the coal 
west of the Rocky Mountains is of this variety. 

As its name denotes, it generally is of brown color 
— although the western coal is black — and has a con- 
choidal fracture. It contains a large quantity of 
water when first mined, as much as 60 per cent, and 
when " air-dry " from 15 to 20 per cent. The per 
cent of ash is also high, from 1 to 20 per cent. 

The average moisture and ash in American lignites 
are 12.75 anc ^ 6.1 respectively. 

The percentage composition of brown coal may be 
considered as approximately, 

Water. Carbon. Hydrogen. Oxygen & Nitrogen. Ash. Sp. Gr. 

German 18.0 50.9 4.6 16.3 10.2 1.3 

Bituminous Coal — This is the variety from which all 
the following coals are supposed to have been formed, 
by a process of natural distillation combined with pres- 
sure. According to the completeness of this process 
we have specimens which contain widely differing quan- 
tities of volatile matter. This forms the true basis for 
the distinguishing of the varieties of coal. In ordinary 
bituminous coal this volatile matter amounts to 30 or 
40 per cent. Three varieties of bituminous coal are 
ordinarily distinguished, as follows: 

* In case the student desires to follow in a more extended mannel 
the geology of coal, reference may be had to Le Conte's " Elements of 
Geology," pp. 345-4*4, 3<* ed. 



74 GAS AND FUEL ANALYSIS. 

Dry or non-caking —those which burn freely with but 
little smoke and — as the name denotes — do not cake 
together when burned. The coals from Wyoming 
are an example of this class. 

Caking — those which produce some smoke and cake 
or sinter together in the furnace. An example of 
these is the New River and Connellsville coal. 

Fat or Long-flaming — those producing much flame 
and smoke and do or do not cake in burning; volatile 
matter 50 per cent or more. Some of the Nova 
Scotia coals belong to this class. 

Bituminous coal varies much in its composition — is 
black or brownish black, soft, friable, lustrous, and of 
specific gravity of 1.25 to 1.5. 

Moisture varies from 0.25 to 8 per cent, averaging 
about 5. 

The percentage composition of bituminous coal may 
be considered as approximately,* 



Water. 


Carbon. Hydrogen. 
77.1 5.2 


Oxygen. Nitrogen. 


Ash. 
7.6 


Sulphur. 
I.O 


Water. 
0.9 


Volatile Matter. 
27.4 


Fixed Carbon. 
64.I 




Ash. 
7.6 



Semi-Biturninous or Semi-Anthracite Coal is upon the 
border-line between the preceding and the following 
variety; it is harder or softer than bituminous, contains 
less volatile matter (15 to 20 per cent), and burns 
with a shorter flame. An example of this is the 
Pocahontas coal. 

The per cottage composition of semi- bituminous l and 
semi-anthracite coal may be considered to be approxi- 
mately,* 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sulphur. 

O.5 83.O 4.7 4.2 1.3 5.5 O.8 

Water. Volatile Matter. Fixed Carbon. Ash. 

o.5 *&-1 77^3 5-5 

* H. J. Williams. 






FUELS— SOLID, LIQUID, AND GASEOUS. 75 

Anthracite Coal is the hardest, most lustrous, and 
densest of all the varieties of coal, having a specific 
gravity of 1.3 to 1.75; it contains the most carbon 
and least hydrogen and volatile matter (5 to 10 per 
cent). It has a vitreous fracture and kindles with 
difficulty, burning with a feeble flame, giving little or 
no smoke and, with sufficient draft, an intense fire. 
The Lehigh coal is an excellent example of this class. 

The percentage composition of anthracite coal may 
be considered as approximately," 

Water. Carbon. Hydrogen. Oxygen. Nitrogen. Ash. Sulphur. 

2.0 83.9 2.7 2.8 0.8 7.2 0.6 

Water. Volatile Matter. Fixed Carbon. Ash. 

2.0 4.3 86.5 7.2 

The ash of coal f varies from 1 to 20 per cent 
and is mainly clay — silicate of alumina — w T ith lime, 
magnesia, and iron. When coal is burned it yields 
from 6100 to 8000 C. and requires about 12 times its 
weight of air, 9.76 cu. m. per kilo or 156.7 feet per 
pound. For the greatest economy Scheurer-Kestner J 
found that this should be increased from 50 to 100 
per cent. • 

Charcoal is prepared by the distillation or ^moulder- 
ing of wood, either in retorts, where the valuable 
by-products are saved, or in heaps. It should be 
jet-black, of bright lustre and conchoidal fracture. 

When wood is charred in heaps only about 20 per 
cent of its weight in charcoal is obtained — 48 bushels 
per cord, or about half the percentage of carbon. 
When retorts or kilns are employed, the yield is in- 
creased to 30 per cent, and 40 per cent of pyroligneous 

* H. J. Williams. 

t Regarding the fusibility of coal ash, see Fieldner, J. Ind. and Eng. 
Chem., 7, 829 (1915): ± Jour. Soc. Chem. Ind.. 7, 616. 



76 GAS AND FUEL ANALYSIS. 

acid of 10 per cent strength, with 4 per cent of tar, 
are obtained. 

The percentage composition of zvood-charcoal may be 
considered as approximately, 

Carbon. Ash. Sp. Gr. 

97.O 3.0 0.2 

Coke is prepared by the distillation of bituminous 
coal in ovens; these are of two types, those in which 
the distillation-products are allowed to escape — the 
14 beehive M ovens — and those in which they are care- 
fully saved, as the Otto-Hoffman, Semet-Solvay, 
Simon-Carves', and others. 

The " beehive" ovens yield from 50 to 65 per 
cent of the weight of the coal — about 2\ tons. The 
Otto-Hoffman ovens are long narrow thin-walled re- 
torts 33 by 6 by 1.5 feet, * regeneratively heated by side 
and bottom flues; the charge is about 6 tons of coal, 
and the following percentage yields of by-products 
are obtained: coke 70-75, gas 16 (10 M. cu. ft.), tar 
3.3-5.6, ammonia 0.3-1.4.-}- The Semet-Solvay ovens 
differ from the above in that they are not regen- 
eratively heated and their walls are thicker, serving to 
store up the heat ; the yield of coke is somewhat 
higher — about 80 per cent.;}; The by-products ob- 
tained alone increase the value of the output about 
one and one half times. Good coke should possess a 
cellular structure, a metallic ring, contain practically 
no impurities, and be capable of bearing a heavy 
burden in the furnace. 

* Irwin, Eng. Mag., Oct. iqoi, abstr. J. Am. Chem. Soc, 24, 40. 
f H. O. Hofman, Tech Quar., IX, 212 (1898). 
\ Pennock, J. Am. Chem. Soc, 21, 678 (1899). 



FUELS— SOLID, LIQUID, AND GASEOUS. 11 

The analysis of Connellsville coke with the coal 
from which it is prepared is given below. 

Water. Volatile Matter. Carbon. Sulphur. Ash. 

Coal I.26 30.I 59.62 O.78 8.23 

Coke O.03 I.29 89.15 0.084 9-52 

Otto-Hoffman coke: 

Fixed Carbon. 
3.7 1.3 86.1 8.9 

Heating value 7100 C. 

The Minor Solid Fuels. 

Sawdust and Spent Tan-bark find occasional use, 
their value depending upon the quantity of moisture 
they contain. With 57 per cent of moisture 1 pound 
of tan-bark gave an evaporation of 4 pounds of water. 

Wheat Straw finds application as fuel in agricul- 
tural districts, 3! pounds being equal to I pound of 
coal. Upon sugar-plantations the crushed cane or 
Bagasse, partially dried, is extensively used as a 
fuel. With 16 per cent of moisture an evaporation 
of 2 pounds of water per pound of fuel has been 
obtained. 

Briquets/' Patent Fuel/'* — In Europe coal dust is 
cemented together with some tarry binding material 
and baked or compressed into blocks usually about 
6X2X1 inches, which form a favorite fuel for domestic 
purposes. In some cases they take the form and size 
of a large goose egg, and are called eggettes: these are 
being made, among other places, at Scranton, Pa., and 
withstand well the shocks incident to shipment. 

* Condition of the Coal Briquetting Industry in the United States, 
E. W. Parker, Bull. No. 316 U. S. Geol. Survey, Contributions to 
Economic Geology, 1906. Part II, Coal Lignite and Peat, pp. 
460-485. 



78 GAS AND FUEL ANALYSTS. 

Storage of Coal and Spontaneous Combustion. — 

While authorities differ as to the way and manner in 
which coal should be stored, as regards height of pile, 
number, size, and arrangement of ventilating channels, 
they are practically agreed that it should always be 
covered. Six months' exposure to the weather may with 
European coals cause a loss of from 10 to 40 per cent in 
heating value, while with Illinois coals it varies from 
2 to 10 per cent.* The North German Lloyd Steamship 
Company stores its coal in a covered bin provided with 
ventilators, and restricts the height of the pile to 8 feet. 
A large gas company in a western city also uses a covered 
bin, with ventilators 8 inches square every 20 feet; the 
height of the pile may be from 10 to 15 feet. An electric 
company in the same city f has arranged to store 14,000 
tons of coal under water in 12 pits, a steam-shovel being 
used to dig out the coal. Ventilating flues serve the 
additional purposes of enabling the temperature of the 
pile to be ascertained before ignition takes place, and as 
a means of introduction of either steam or carbonic acid 
to extinguish any fire which may occur. All the supports 
of the bin in contact with the coal should be of brick, 
concrete or iron, and if of hollow iron, filled with cement. 
The spontaneous combustion of coal is due primarily 
to tne rapid absorption of oxygen by the finely divided 
coal, and to the oxidation of iron pyrites, "coal brasses/' 
occurring in the coal. The conditions favorable to 
the process are: 

* Parr and Hamilton, Univ. of 111., Bulletin 4, No. 33 (1907). See 
also Bull. 136, Bureau of Mines, Deterioration of Coal during Storage 

(1017). 

f Eng. and Min. Jour., September 15, 1906. 



FUELS— SOLID, LIQUID, AND GASEOUS. 79 

First. A supply af air sufficient to furnish oxygen, but 
of insufficient volume to carry off the heat generated. 

Second. Finely divided coal, presenting a large surface 
for the absorption of oxygen. 

Third. A considerable percentage of volatile matter in 
the coal. 

Fourth. A high external temperature. 

A method of extinguishing a fire in a coal pile not 
provided with ventilators consists in removing and spread- 
ing out the coal and flooding the burning part with water. 
Another method consists in driving a number of iron or 
steel pipes provided with " driven well points" at the 
place where combustion is taking place, and forcing 
water or steam through these upon the fire. 

b. Liquid Fuels.* 

These consist of petroleum and its products, and 
various tarry residues from processes of distillation, 
as from petroleum, coking-ovens, wood and shale. 
Liquid fuel possesses the advantage that it contains no 
ash, is easily manipulated, the fire is of very equable 
temperature, very hot, and practically free from smoke. 

Regarding the origin of petroleum, many theories 
have been proposed. That of Engler,f that it was 
formed by the distillation under pressure of animal fats 
and oils, the nitrogenous portions of the animals pre- 
viously escaping as amines, seems most probable; it 
has yielded the best results of any hypothesis when 
tested upon an industrial scale. 

* For the heating value of liquid fuels, see Table V; for their specifi- 
cation, see p. 144. 

t Jour. Soc. Chem. Industry, 14, 648. 



80 GAS AND FUEL ANALYSIS. 

Crude Petroleum varies greatly in color according 
to the locality; it is usually yellowish, greenish, or 
reddish brown, of benzine-like odor, and sp. gr. of 0.78 
to 0.80. It " flashes" at the ordinary temperature; 
hence great care should be employed in its use and 
storage. \te percentage composition is shown below. 

Carbon. Hydrogen. 

84.O-85.O 16. 0-15.O 

It is more than twice as efficient as the best anthra- 
cite coal. In practice 14 to 16 pounds of water per 
pound of petroleum have been evaporated, and an 
efficiency of 19,000 B. T. U. was obtained as against 
8500 B. T. U. for anthracite. In general 3i to 4 bar- 
rels of oil are equivalent to a ton of good soft coal.* 

c. Gaseous Fuels. 

Natural Gas is usually obtained when boring for 
petroleum and consists mainly of methane and hydro- 
gen, although the percentage varies with the locality. 
The Findlay, Ohio,f gas is of the following composi- 
tion: 



CH 4 


H 


N 


O 


C a H 4 


co a 


CO 


H 2 S 


Sp Gr. 


92.6 


2.3 


3.5 


0.3 


0.3 


0.3 


0.5 


0.2 


0.57 



Blast-furnace, Producer, or Generator Gas is the 

waste gas iss'iing from the top of a blast-furnace or ob- 
tained by partially burning coal by a current of air (pro- 

* W. B. Phillips, Texas Petroleum (1900), p. 84. 
f Orton. Geology of Ohio, vol vi. p. 137. 



FUELS—SOLID, LIQUID, AND GASEOUS, 8 1 

duced by steam) in a special furnace — a gas-producer or 
generator. It is mainly carbonic oxide and nitrogen. 









CO 


N 


co 2 


H 


CH 4 





B.T.U. per 
Foot. 


Blast-fur 


nace gas. 
i bitumin. 

CI 

anthrac. 




34 3 
24-5 
25.0 
27.0 


63-7 
46.8 
41.4 
57-3 


0.6 

3-7 
4.o 
2..S 


1.4 

17.8 
I9.4 
I2.0 


6.8 
9.6 
1.2 


0.4 
0.6 


122 


Gas froir 
ii (i 

u a 


coal 

a 


2*3 


ii it 

ii ii 


ci 

a 


a 
a 


17.2 
26.0 


53-i 
47.o 


8.6 
8.0 


18.2 
18.5 


2.4 
0.5 


0.4 


I40 
145* 



One ton of coal yields from 1 60 1 to 170 thousand 
cubic feet of gas of 1 56 to 138 B.T.U. heating power, or 
81 to 86 or even 90 per cent of the value of the coal. 

Water-gas. — If, instead of passing simply air over 
hot coal, water-vapor, or rather steam, be employed, 
it is decomposed, giving carbonic oxide and hydrogen, 
according to the equation H Q + C = CO + H, , and 
the resulting mixture is called water-gas. The per- 
centage composition, which varies according to the ap- 
paratus and fuel employed, is about as follows: 

CO H CH 4 CO, N O lilts. Sp. Gr. 

From coke 45.8 457 20 4.0 2.0 0.5 — 0.57 

From bit. coal 34.0 41.9 7.5 5 4 9.2 1.1 0.9 — 

Fischer J states that 1 ton of coke gives about 36 
thousand cubic feet of gas, equivalent to 42 per cent 
of the value of the coal. From I ton of bituminous 
coal about 51 thousand cubic feet of gas of 360 B.T.U. 
heating power are obtained, or an efficiency of nearly 
62 per cent.§ 



* Suction gas producer. 

f Humphrey, Jour. Soc. Chem. Industry, 20, 107 (1901); ibid.) 16, 

522 (1897'. 

J Taschenbuch fur Feuerungs-Techniker, p. 27. 
§ Slocum, J. Soc. Chem. Industry, 16, 420 (1897). 



82 



GAS AND FUEL ANALYSIS. 



Coal or Illuminating Gas was formerly produced 
by the distillation of bituminous coal; it is at present 
largely made by the enriching of water-gas. "Gas- 
oil," a crude naphtha, is blown into the water-gas 
generator and changed to a permanent gas by the 
heat. It is of the following composition : 

H CH 4 CO C 3 H 4 CO a N O Sp. Gr. 

Coal gas 47.0 40.5 6.0 4.0 0.5 1.5 0.5 0.4 

Enriched water-gas 27.9 25.9 25.3 15.0 2.9 3.0 0.0 0.6 

One ton of coal gives about 10 thousand cubic feet of 
gas, or about 20 per cent of the heating value of the 
coal. 

Heating Value of these Gases. 

The following table, mainly from Slocum,* gives an 
idea of the comparative value of the gases: 

Air Required /or 
Name of Gas. Vu'.F.r Yield - ^ScTfe 

Oil 1350 77 cu. ft. .... 

per gal. 
Natural 980 .... 9.80 

840-1170 

Thousand Ft. 
per Ton. 

Enriched water 700 40}: .... 

Coke-oven 686 5 .... 

Coal 600-625 10 5.65 

Blue water 332-5°° 5 .... 

Heating (coke-oven). 367 5 .... 

Bit. coal water 342 51 2.97 

Mond producer 156 160 1.25 

Siemens producer. ... 137 170 .... 

Wood or peat 140-145 .... .... 

* Slocum, J. Soc. Chem. Industry. 16, 420 (1897). 

f Determined with the Junkers calorimeter. 

J 168-200 gallons of " gas-oil " are also required. 



FUELS— SOLID, LIQUID, AND GASEOUS. 83 

References. — Report of U. S. "Liquid Fuel" Board, 
Dept. of Navy, Bureau of Steam Engineering, Washington, 
1904. pp. 450. 

Report on the Operations of the Coal-Testing Plant of 
the U. S. Geological Survey at St. Louis, 1904. Pro- 
fessional Paper, No. 48, Parts I, II, and II. 1906. 

Preliminary Report on the Operations of the Coal Testing 
Plant of the U. S. Geol. Survey at St. Louis, 1904. 

Bull. No. 261, 1905. 

Bull. No. 261 for 1905. 

Bull. No. 290, 1906. 

A Study of Four Hundred Steaming Tests, made at 
Fuel Testing Plant at St. Louis in 1904, 1905, 1906, by 
L. P. Breckenridge. Bull. No. 325, U. S. Geol. Survey, 
1907. 

The Burning of Coal without Smoke. D. T. Randall. 
Bull. No. 334, U. S. Geol. Survey, 1908. 

Barr, " Boilers and Furnaces." 

Hodgetts, "Liquid Fuels." 

Pratt, "Principles of Combustion in the Steam Boiler 
Furnace." Babcock & Wilcox Co., 1919. 

Uehling, "Chemical and Physical Control of Boiler 
Operation." Power, 49, 32 (1919). 

"Cost of Steam from Coal." Power, 42, 456 (1915). 

"Saving Coal in Boiler Plants." Bureau of Mines 
Technical Paper, 205 (1918). 

Moore, "Liquid Fuels for Internal Combustion En- 
gines," (19 1 8). 

Maujer and Bromley, "Fuel Economy in Boiler Rooms " 

(r 9 i8). 

Wadsworth, " Efficiency in the Use of Oil Fuel," Bureau 
of Mines (19 18). 



CHAPTER VIII. 

METHODS OF ANALYSIS AND DETERMINATION 
ON THE HEATING VALUE OF FUEL. 

SAMPLING. 

A FEW representative lumps or shovelfuls are taken 
from each barrow or from various points in the pile 
in boiler tests. Shovelfuls of coal should be taken at 
regular intervals and put into a tight covered barrel 
or some air-tight receptacle, and the latter should be 
placed where it is protected from the heat of the fur- 
nace.* In sampling two conditions must be observed: 
First, the original sample should be of considerable size 
and thoroughly representative; and, second, the quartering 
down to an amount which can be put into a sealed "light- 
ning" jar should be carried out as quickly as possible 
after the sample is taken. Careful samplings and careful 
treatment of samples are necessary to obtain reliable 
results, especially in the determination of moisture. 
The lumps are coarsely broken, and the whole spread 
out in a low circular heap. Diameters are drawn 
at right angles in it and opposite quarters taken, 
and treated similarly to the whole sample. The 
operation is continued until a sample of a few pounds \ 
is obtained. This is roughly crushed and samples 
taken at different points for the moisture determi- 

* Report of Committee on Coal Analysis, J. Am. Chem. Soc, 21, 
1116 et seq. (1899). 

t If the largest lump be \ inch, 9 pounds; a less quantity as the lumps 
grow smaller. 

84 






FUEL ANALYSIS— HEATING VALUE. 85 

nation ; it is then further quartered down until a sample 
of 100 grams which passes a 60-mesh sieve is obtained. 
The methods employed in the analysis of fuels are 
largely a matter of convention, various methods giving 
varied results ; for example, it is well-nigh impossible 
to obtain accurately the percentage of moisture in 
coal, as when heated sufficiently hot to expel the 
water some of the hydrocarbons are volatilized. 

Moisture. — Dry one gram of coal in an open cru- 
cible at I04°-I07° C. for one hour. Cool in a desic- 
cator and weigh covered. Where accuracy is required, 
determinations must also be made on the coarsely 
ground sample ; this latter result is to be regarded as 
the true amount and corrections applied to all deter- 
minations where the powdered sample is used.* f J 

Volatile Combustible Matter and Coke.*§ — Place 
one gram of fresh, undried powdered coal in a platinum 
crucible having a capsule cover. Heat over the full 
flame of a Meker burner for seven minutes by the watch. 
The crucible should be supported on a platinum triangle 
with the bottom 1 centimeter above the top of the 
burner. The flame should be not less than 15 cm. high 
X25 cm. in diameter when burning free, and the deter- 
mination should be made in a place free from drafts. 
The upper surface of the cover should burn clear, but 
the under surface should remain covered with carbon. 
To find " Volatile Combustible Matter " subtract the 
per cent of moisture from the loss found here. The 

* Report of Committee on Coal Analysis, J. Ind. and Eng. Chem. 5, 
522 (1913). 

t See also an article by Hale, Proc. Am. Soc. Mech. Eng., 1896. 

X Variation allowed in check analyses 0.2-0.3 P er cent. 

§ Sommcrmeier, J. A. C. S., 28, 1002 (1906). 



86 GAS AND FUEL ANALYSIS. 

residue in the crucible minus the ash represents the 
Coke or Fixed Carbon. 

Certain non-coking coals suffer mechanical loss from 
the rapid heating.* Lignites should be heated for five 
minutes previously by playing the burner on the crucible. 
Carbon. — Marks f has shown how to calculate the 
total per cent of carbon in the coal, from the proximate 
analysis, i.e., the coke and volatile matter. This requires 
the calculation of the per cent of carbon in the vola- 
tile matter, and is done as follows: Coke + volatile mat- 
ter = combustible. % vol. matter in combustible = 
% vol. matter 
% combustible (coke + vol. matter) 
With this (vol. matter in combustible) as an abscissa 
(horizontal distance) locate in Fig. 19 the corresponding 
ordinate, which is the per cent of volatile carbon in the 
combustible matter. Multiply the latter by the per 
cent combustible in the coal, divide by 100 and find the 
per cent of volatile carbon in the coal; i.e., the per- 
centage of carbon in the volatile matter. An illus- 
tration will make this clear. Taking the composition 
of the bituminous coal (p. 74) as volatile matter 27.4, 
fixed carbon 64.1. Fixed carbon + volatile matter is 
64.1 + 27.4 = 91.5%. 
%vol. matter 27.4 _ 

% combustible 91.5 
30% vol. matter combustible. 
The corresponding ordinate, Fig. 19, is 15.5, which is 
the per cent of volatile carbon in the combustible. 

* Variation allowed in check analyses 0.5-1.0%. 
t Tower, 37, 55 (1913)- 



FUEL ANALYSIS— HEATING VALUE. 



87 



Since the coal is but 91.5 per cent, combustible, the 
volatile carbon in the coal is 91.5 per cent of this, 



30 
































































































































































































25 
































































































































































































2 
















































1 20 

g 






























































































8 

































































































+> 
a 
















































15 
* 






























































































6 

































































































O 
















































-10 


























































/ 

















































/ 




































& 

fr 
















































































































































5 


















































































































































































































































J.0 20 30 40 50 

Per cent Volatile Matter in the Combustible* 

Fig. 19. — Marks' Chart for Carbon in Coal. 

15. 5X 9 =14.2. This added to the fixed carbon, 

100. o 

64.1 + 14.2^78.3 per cent, gives the per cent of carbon 



88 



GAS AND FUEL ANALYSIS. 



in the coal ; the results of the ultimate analysis showed 
77.1 per cent. 

Carbon and Hydrogen. — These are determined by 
burning the coal in a stream of air and finally in 
oxygen, the products of combustion, carbon dioxide 
and water, being absorbed in potassium hydrate and 
calcium chloride. 

Apparatus Required. — Combustion-furnace similar 
to that shown in Fig. 20. Combustion-tube filled. 




Fig. 20. — Combustion-Furnace. 

Potash-bulbs with straight chloride of calcium tube 
filled. Chloride of calcium tube filled. Oxygen- 
holder, drying and purifying apparatus. Porcelain 
boat, desiccator, tongs, |-inch rubber tubing. Ana- 
lytical balance. 

The combustion-tube is of hard glass, \ inch in in- 
ternal diameter and 36 inches long, closed with per- 
forated rubber stoppers. One end — called the front 
end — is filled with a layer of copper oxide 12 inches 
long, held in place by plugs of asbestos coming 






FUEL ANALYSIS— HEATING VALUE, 89 

within 4 inches of the stopper. In coals rich in sul- 
phur the oxide is partially replaced by a layer of 
chromate of lead 2 inches long. The position of the 
boat containing the coal is immediately behind this 
copper oxide; behind the boat is placed an oxidized 
copper gauze roll, 6 inches long. Before making the 
combustion, the tube and contents should be heated 
to a dull red heat in a stream of oxygen freed from 
moisture and carbon dioxide by the purifying appa- 
ratus, to burn any dust and dry the contents; it is 
then ready for use. 

The potash-bulbs are an aggregation of five bulbs, 
the three lowest filled with potassium hydrate of 1.27 
sp. gr., the other two serving as safety-bulbs, pre- 
venting the liquid from being carried over into the 
connectors. They should be connected further with a 
chloride of calcium tube to absorb any moisture carried 
away by the dry gas. When not in use they should 
be closed with connectors carrying glass plugs. Before 
weighing they should stand at least fifteen minutes in 
the balance-room to attain its temperature ; the weight 
should be to milligrams and without the connectors. 

The chloride of calcium tube is of U form, provided 
with bulbs for the condensation of the water; the 
granular calcium chloride is kept in place by cotton 
plugs, and the stopper neatly sealed in with sealing- 
wax. As calcium chloride may contain oxide which 
would absorb the carbon dioxide formed, a current of 
dry carbon dioxide should be passed through the tube 
and thoroughly swept out by dry air before use. 

The chloride of calcium tube like the potash-bulbs 
should be placed in the balance-room fifteen minutes 



90 GAS AND FUEL ANALYSIS. 

before weighing and, if the balance-case be dry, may 
be weighed without the connectors. It should be 
weighed to milligrams. 

The oxygen-holder may be like the Muencke aspi- 
rator, Fig. 1 8. The oxygen should be purified by passing 
through potassium hydrate and over 'calcium chloride. 

Operation. — The front stopper of the combustion- 
tube is slipped carefully upon the stem of the chloride 
of calcium tube and this connected to the potash- 
bulbs; 0.2 to 0.3 gram of the coal is carefully 
weighed into the porcelain boat (to o. 1 mg.), the roll 
removed, and the boat inserted behind the layer of 
copper oxide, and the roll and stopper replaced. 
The tube is now ready to be heated. 

The front of the copper oxide is first heated, the 
heat being gradually extended back; at this time the 
rear end of the copper roll is heated and a slow cur- 
rent of purified air passed through. This method 
of gradual heating of the tube is followed until the 
layer of copper oxide and the rear portion of the roll 
are at a dull red heat. Heat is now cautiously applied 
to the coal and the current of air slackened. The 
volatile matter in the coal distils off, is carried into 
the layer of copper oxide and burned; the carbon 
dioxide formed can be seen to be absorbed by the 
potassium hydrate. When this absorption almost 
ceases, oxygen is turned on and the coal heated until 
it glows. The stream of oxygen should be so regulated 
as to produce but two bubbles of carbon dioxide in 
the bulbs per second. If the evolution be faster, the 
gas is not absorbed. When the coal has ceased glow- 
ing, oxygen is allowed to pass through the apparatus 



FUEL ANALYSIS— HEATING VALUE.^ 91 

until a spark held at the exit of the last chloride of 
calcium tube (on the bulbs) re-inflames; the oxygen is 
allowed to run for fifteen minutes longer. The current 
of oxygen is now replaced by purified air, and the 
heat moderated by turning down the burners and 
opening the fire-clay tiles; the air is allowed to run 
through for twenty minutes to thoroughly sweep out 
all traces of carbon dioxide and moisture. The bulbs 
and U tube are disconnected, stopped up, allowed to 
stand in the balance-room, and weighed as before. 
The increase in weight in the bulbs represents the 
carbon dioxide formed; this multiplied by the factor 
O.2727 gives the carbon. Similarly the increase in the 
U tube, minus the water due to the moisture in the 
coal, represents the water formed, one ninth of which 
is hydrogen. 

Notes. — At no time in the combustion should any 
water appear near the copper roll, as it is an indication 
that the products of combustion have gone backward 
into the purifying apparatus and hence are lost. Such 
analyses should be repeated. Should moisture appear 
in the front end, it may be gently heated to expel it. 
Both ends of the tube should be frequently touched 
with the hand during the combustion, and should be 
no hotter than may be comfortably borne, as the 
stoppers give off absorbable gases when highly heated. 
Care should be taken not to heat the tube too hot, 
fusing the copper oxide into and spoiling it. One 
tube should serve for a dozen determinations. It 
should not be placed upon the iron trough of the 
furnace, but upon asbestos-paper in the trough, to 
prevent fusion to the latter. 



92 GAS AND FUEL ANALYSIS. 

As will be seen, the execution of a combustion is not 
easy, and should only be intrusted to an experienced 
chemist. The results are usually o.i per cent low for 
carbon and a similar amount high for hydrogen. 

Ash. — This is determined by weighing the residue left 
in the- boat after combustion, or by completely burning 
r gram of the coal contained in a platinum dish. ] 

Nitrogen is determined by Kjeldahl's method, which 
consists in digesting the coal with strong sulphuric acid, 
aided by potassium permanganate, until nearly colorless. 
The nitrogenous bodies are changed to ammonia, forming 
ammonium sulphate and are determined by rendering 
alkaline and distilling the solution. 

Sulphur is determined by Eschka's method, con- 
sisting in heating for an hour one gram of the coal mixed 
with one gram of magnesium oxide and 0.5 grm. sodium 
carbonate in a platinum dish without stirring, using an 
alcohol-lamp, as gas contains sulphur. It is allowed 
to cool and rubbed up with one gram of 'ammonium 
nitrate and heated for 5 to 10 minutes longer. The 
resulting mass is dissolved in 200 cc. of water evaporated 
to 150 cc, acidified with hydrochloric acid, filtered, and 
sulphuric acid determined in the filtrate in the usual 
way with barium chloride. Or the washings of the 
bomb calorimeter may be used (see liquid fuels). 

Oxygen is determined by difference. 

For Coal Specifications see Appendix, p. 133. 

For a ready method of calculating cost per million 
B.t.u.,"see Blake, J. Ind. andEng., 10, 627 (1918). 

Note. — The foregoing methods are technical, but of sufficient accuracy 
for most purposes. For more accurate and later methods see the Report 
of the A. C. S. in J. Ind. and Eng. Chem., 5, 517, et seq. 



FUEL ANALYSIS— HEATING VALUE. 93 

ANALYSIS OF LIQUID FUELS.* 

Carbon and Hydrogen. — This determination is made 
as in the case of the solid fuels, the liquid being con- 
tained in a small bulb sealed for weighing to prevent 
volatilization. The stem is scratched and broken off 
and the bulb inserted in the combustion tube in place of 
the boat. Extra care in heating has to be observed to 
prevent the liquid from passing through unburnt. For 
thick or tarry oils having a small quantity of volatile 
matter, the boat may be used as with solid fuels. 

Sulphur. — The method consists in burning the oil in a 
small lamp and collecting the products of combustion. 
The lamp is a miniature " oil lamp " made from a 3-inch 
test-tube (weighing tube) by drawing a piece of weighed 
lamp wicking through a small glass tube contained in the 
stopper. This lamp is suspended by a wire from the 
balance and weighed accurately. 

It is lighted and hung under a funnel arranged so that 
the products of combustion are drawn by an air-pump 
through a series of two washing bottles containing satu- 
rated bromine water. After about a gram of oil has been 
burned (about 1.3 cc.) the wick is carefully removed 
without losing any oil, the stopper replaced and the tube 
again weighed. The wick and oil it contains are covered 
with Eschka's mixture and treated as for the determina- 
tion of sulphur in coal (p. 92). The hydrochloric acid 
filtrate is added to the bromine solution, the bromine 
boiled out, the solution evaporated to about 150 cc, and 
the sulphuric acid formed determined in the usual way 
with barium chloride. The oil burned is obviously the 
weight of the lamp before and after burning less the weight 

* For Fuel Oil Specifications, see Appendix, p. 144* 



94 



GAS AND FUEL ANALYSIS. 



of the dry wick. This treatment of the wick is necessary, 
as Conradson * has found sometimes 40 per cent of the 
sulphur in the wick. 

By the Calorimeter. — After oil is burned in the bomb 
calorimeter (p. 96), it is thoroughly washed out with 
distilled water, and 6-8 cc. of HC1 1 : 1 with a few drops 
of bromine water added, the solution heated to boiling 
and filtered; the filter is washed free of sulphates, the 
filtrate made just neutral with NaOH or Na 2 C0 3 , 1 cc. 
normal HC1 added and the sulphates determined in the 
usual way with barium chloride or with the turbidimeter. 
If any odor be detected in the gases escaping from the 
bomb, the determination must be repeated, using a pressure 
of 25 atmospheres of oxygen with a bomb of 400-600 cc. 
capacity. The sulphur is usually a trifle low. 

Barlow's f method is excellent, but requires consider- 
able experience to carry out. 

Nitrogen is determined exactly as in the case of solid 
fuels. 

Water can be shown qualitatively by the eosine test, J 
by rubbing with a little eosine on a glass plate. If water 
be present the oil will take on a pink color. It is quan- 
titatively determined § by diluting the oil with ^n equal 
volume of benzole and whirling it in a centrifuge until 
the separated layer of water does not appear to increase 
in volume. The benzole should have been thoroughly 
shaken with water and centrifuged at the same tem- 
perature for the same length of time in order to saturate 
the benzole with water. 

* J. Ind. and Eng. Chem., 2, 171 ^1910). 

t J. Am. Chem. Soc, 26, 341 (1904). 

% Holley and Ladd, Mixed Paints, Color Pigments and Varnishes, p. 36. 

§ Charitschkoff, Chem. Zeit., 33, 93 (1906). 



FUEL ANALYSIS— HEATING VALUE. 95 

Flash and Fire Test. — Determined by heating the 
oil in the covered New York tester or lubricating oil tester 
according to Gill, " Short Handbook of Oil Analysis," 
Chapters I and II. 

The analysis of gaseous fuels * has already been de- 
scribed in Chapter V. 

DETERMINATION OF CALORIFIC POWER OF SOLID 
AND LIQUID FUEL 

a. Direct Methods. 

Many forms of apparatus have been proposed 
for this purpose; few, however, with the exception of 
those employing Berthelot's principle — of burning the 
substance under a high pressure of oxygen — have yielded 
satisfactory results. The apparatus of William Thom- 
son,! and also that of Barrus, in which the coal is burnt 
in a bell-jar of oxygen under water, while usually yield- 
ing results within 3 per cent of the calculated value, yet 
they may vary as much as 8 per cent from that value. J 
Unless a crucible lined with magnesia be used, or the 
sample mixed with bituminous coal, it is inapplicable 
to certain semi-bituminous and anthracite coals, as the 
ash formed over the surface prevents the combustion of 
the coal beneath it. 

Fischer's calorimeter § is similar in principle, but is 
claimed to give very good results. || 



* For the determination of gasolene vapor in gaseous mixtures, see 
Scott, " Standard Methods of Chemical x\nalysis," or Bureau of Mines 
Technical Paper, 115. 

t Thomson, Jour. Soc. Chemical Industry, 5, 581. 

} Ibid., 8, 525. 

§ Zeit. f. angewandte Chemie, 12, 351. 

II Bunte, Jour. f. Gasbeleuchtung und Wasserversorgung, 34, 21, 41. 



96 GAS AND FUEL ANALYSIS. 

Lewis Thompson's calorimeter, in which the coal is 
burnt in a bell-jar by the aid of oxygen furnished by 
the decomposition of potassium chlorate or nitrate, is 
open to several objections, the chief of which are: 
i. The evolution of heat due to the decomposition of the 
oxidizing substance used. 2. Loss of heat due to mois- 
ture carried off by the gases in bubbling through the 
water. The results which it gives must be increased by 
15 per cent.* 

HempePs apparatus f makes use of the Berthelot 
principle: the coal must be compressed into a cylinder 
for combustion — a process to which every coal is not 
adapted — only applicable to certain varieties of bitumin- 
ous and brown coal. The mixture with the coal of any 
cementing or inflammable substance to form these cylin- 
ders carries with it the necessity of accurately determining 
its calorific power beforehand. 

Numerous other workers have experimented with the 
bomb calorimeter, Mahler, Atwater, Kroecker, Williams, 
Norton, Parr and Emerson; as the last apparatus is now 
in common use it will be described here. J 

Details of Emerson Apparatus. 

Bomb. — The bomb is made of steel, consisting of two 
cups joined by means of a heavy steel nut. The cups 
are machined at their contact faces with a tongue and 
groove, the joint being made tight by means of a lead 
gasket inserted in the groove. The lining is of sheet 

* Scheurer-Kestner, J. Soc. Chem. Industry, 7, 869 (1888). 

f Hempel, Gasanalytische Methoden, p. 347. 

X From the circular accompanying the apparatus. 



FUEL ANALYSIS— HEATING VALUE. 



97 



metal, usually pure nickel, although gold and platinum 
are sometimes used, spun to fit the interior. The bomb is 







EMERSON-FUEL-CALORIMETER 
Fig. 21. 



made up tight with a milled wrench or spanner. The 
pan holding the combustible is of platinum or nickel, 
and the supporting wire of nickel. The fuse wire should 



98 GAS AND FUEL ANALYSIS. 

be platinum in general fuel testing. In standardizing 
the calorimeter by means of cane sugar, benzoic acid, 
etc., it is necessary to use iron fuse wire. 

Calorimeter. — The jacket is either a double-walled 
copper tank, between the walls of which water is inserted, 
or a vacuum- walled cup. The calorimeter bucket proper, 
inside this, is made as light as possible of sheet brass. 

Stirring Device. S, Fig. 21. — This consists of a paddle- 
wheel shaft enclosed in a vertical tube to facilitate its 
action in circulating the water. The stirrer shaft is 
driven by a belt from a small motor at the other end of the 
stirrer bracket. The motor is mounted on a sliding plate 
which permits of varying the tension on the belt. This 
varying tension serves to regulate the speed of the paddle 
shaft by thus varying the speed of the motor. The 
stirrer is mounted on a post on the calorimeter jacket, as 
is the thermometer holder. 

The motor is driven from a no- volt circuit, and should 
be placed in series with a 60-watt lamp. If so desired, a 
motor driven by a battery can be specified in ordering 
the apparatus. The battery motor is driven by a six- 
volt storage battery. These motors designed for the no- 
volt power circuit may be driven on other voltage pro- 
vided that a proper resistance be placed in series so that 
the current in the circuit is one-half ampere. The motor 
may be driven by either direct or a 60-cycle alternating 
current. 

Oxygen Piping. Fig. 22. — The piping for the insertion 
of oxygen under pressure is made especially strong and 
durable. The piping of small internal bore is made of 
heavy brass. The system is fitted with a hand nipple at 
one end to make the connection with the bomb, and the 



FUEL ANALYSIS— HEATING VALUE. 



99 



other end has a special fitting to grasp the oxygen supply 
tank.* Commercially pure oxygen, free from all traces 
of combustible gases, should be used. 

Iron Plate Holder. — The plate holder or vise is to be 
used when tightening the nut of the bomb with the spanner. 

Swivel Table. — The table with the rotating top is to 
hold the bomb when the same is connected to the oxygen 



C—__ j""L.— -- « /Leaf her 
* r V Washer 




Fig. 22. 

piping. (See Fig. 22.) This swivel table is not included 
with the double outlet bomb. 

Spanner. — The spanner or wrench is a forging with 
30-inch handle and is used to make bomb up with gas- 
tight joint. 



* Furnished by the S. S. White Dental Manufacturing Company. 
Piping to fit other tanks can be furnished to order. 



ioo GAS AND FUEL ANALYSIS. 

Thermometer Telescope. — Hand telescope to enable 
operator to read thermometer to T oVo or T o 2 oo of a 
degree. 

Determination of Heat of Combustion of Fuels 
and Other Combustibles. 

Coal. 

Manipulation. — Place the lower half of the bomb in 
the iron plate holder and adjust the fuel pan support in 
proper position. This support is held by a taper pin 
which fits into the inner end of the insulation plug, which 
plug is at the side of the lower cup of the bomb. The 
taper pin holding the fuel pan support should be entered 
firmly into the porcelain plug in order that the support 
will not permit of tipping, which would likely result in 
the upsetting of the charge of fuel at the time of ignition. 
To enter the taper pin in place, use the small steel spanner 
which fits into the recess of the taper pin. This spanner 
will also be found suitable for removing the taper pin 
from the plug. Care should be taken on the interior of the 
bomb that the linings do not touch the metal part of the insu- 
lation taper pin which holds the fuel pan support. 

The fuse wire is connected to the binding post on the 
fuel pan support and extends across the bomb to the bind- 
ing post at the opposite side of the bomb, sufficient length 
being allowed that the wire will dip down sufficiently to 
be in contact with the fuel which is afterwards placed in 
the pan. Care must be taken that the wire does not touch 
the fuel pan. 

The fuel used is sampled, crushed, and powdered 
according to directions given on page 84. 



FUEL ANALYSIS— HEATING VALUE. ioi 

Fill a test-tube or convenient weighing vial with the 
prepared sample and weigh it accurately to one-tenth of a 
milligram. Pour from this into the pan in the bomb until 
the pan is approximately half full. Weigh the vial again 
and the difference of the above weighings gives us the net 
quantity of fuel in the bomb. This weight should be 
greater than five-tenths of a gram, and not more than one 
and two-tenths grams. For hard coal the maximum 
charge should be not greater than one gram. Hard coal 
should not be as finely divided as soft coal. (Through an 
8o-mesh sieve is sufficient.) 

The upper half of the bomb is placed in position and 
the nut screwed down as far as may be by hand, care 
being taken not to cross the threads. The shoulder on the 
upper half of the bomb over which the nut makes bearing 
contact should be thoroughly lubricated with oil. Extreme 
care should be taken that no oil or grease is deposited on 
the lead gasket, as the bomb, when working properly, 
closes without the upper half turning on the gasket on 
account of the contact friction of the nut. Any oil on 
the lead gasket would tend to hinder the proper action in 
this respect. 

The large wrench is used to make the joint tight, and 
operator should apply the same very nearly to his full 
strength. (If the thread of the large nut is kept free from 
dirt, it will turn into place freely by hand.) 

The bomb is now ready to be filled with oxygen, and 
this is accomplished by means of the spindle valve at the 
top of the bomb. The nipple is coupled to the oxygen 
piping by means of the attached hand union, the bomb 
resting on the swivel table. (The oxygen piping should be 
properly located and screwed fast to the bench.) The 



102 GAS AND FUEL ANALYSIS. 

screw holes in the feet of the sv/ivel table are left large and 
are made for round-head screws so as to allow for adjust- 
ment relative to the oxygen piping. Both should be fixed 
in position. In ftandling the bomb, care should be taken 
not to tip or jar it, as fuel may be thrown from the pan. 

The spindle valve on the bomb need only be opened 
one turn, and then the valve on the oxygen supply cylinder 
is very cautiously opened. The pressure gauge should be 
carefully watched and the cylinder valve so regulated 
that the pressure in the system shall rise very gradually. 
When the pressure reaches 300 pounds per square inch, 
the cylinder valve is closed, and then the spindle valve 
on the bomb immediately after. 

The bomb should be immersed in water immediately 
to detect any possible leakages. (Preferably a glass jar, 
as slight leaks are detected by looking from all sides.) 

The bomb is now ready for the calorimeter, which is 
prepared as follows : 

Nineteen hundred grams of water are placed in the 
calorimeter can at a temperature about i^° below the 
jacket temperature (which temperature should be in 
the proximity of the room temperature.) The bomb is 
then placed in the can; care should be taken that the 
outer surface of this can is thoroughly dry; the stirrer 
and thermometer are lowered into position as indicated 
by the illustration. The thermometer is immersed about 
3 inches in the water and the thermometer bulb should 
be at least J inch from the bomb. Care should be taken 
that the bomb does not touch the sides of the can or that 
the stirrer does not touch the bomb. 

Ignition Wiring. — One terminal of the electric circuit 
for igniting the charge is connected to the bomb by means 



FUEL ANALYSIS— HEATING VALUE. 103 

of the taper binding post which fits into the spindle at 
the top, and the other is connected to the outer end of 
the insulation plug on the lower cup ot the bomb. A 
short length of insulated wire, which is connected to a 
small taper pin fitting into the outer end of the insulation 
plug, is included with the apparatus. The other end of 
this piece of insulated wire is fitted with a connector for 
one terminal from the switchboard. This last-mentioned 
taper pin is fitted into the plug before the bomb is lowered 
into the calorimeter bucket. Two 100-watt lamps in 
parallel are placed in series with the fuse wire when 110- 
volt circuit is used for firing. 

The Run. — The stirrer is started, and allowed to run 
three or four minutes to equalize the temperature through- 
out the calorimeter.* 

Readings of the thermometer are taken for five minutes 
(reading to the two or two °f a degree every minute), 
at the end of which time the switch is turned on for an 
instant only, which will be found sufficient to fire the 
charge. Iji course of a few seconds the temperature begins 
to rise rapidly and readings are taken every half minute 
from the time of firing. After a maximum temperature 
is reached and the rate of change of temperature is evi- 

* If the stirrer gives trouble by refusing to run at sufficient speed or 
by stopping completely, the difficulty is usually due to the accumulation 
of oil on the commutator The operator can readily remove the oil 
with chamois cloth and by using care, this removal of the oil from the 
commutator can be accomplished when the stirrer is running. Draw the 
chamois tightly over the forefinger and press gently on the surface of the 
commutator, taking care not to injure the brushes. 

If the stirrer runs at too high speed causing the water in the calorimeter 
can to be thrown about, a rheostat placed in series with the motor will 
serve to regulate and modify the speed. 



104 GAS AND FUEL ANALYSIS, 

dently due only to the radiation to or from the calorimeter, 
the readings are continued for an additional five minutes, 
reading every minute. These readings before the firing 
and after the maximum temperatures are necessary in the 
computation of the cooling correction. The time elapsed 
from the time of firing to the maximum temperature should 
be in no case more than six minutes. 

When through with run, replace bomb in the holder and 
allow the products of combustion from within to escape 
through the valve at the top of the bomb. Unscrew the 
large nut and clean the interior of the bomb. The inside 
of the nut should be kept oiled ; and also the threaded part 
at the top of the lower cup. 

Immediately after each run the inside of the bomb should 
be dried out with a cloth. The lining of the lower cup 
is removed by withdrawing the fuse-wire binding post 
which is held in place with a taper fit and is easily removed. 
The lining to the upper cup is held in place by the small 
screw at the top which holds the deflector. 

After each day's run the linings should be removed and 
the inner surface of the bomb under the linings should be 
coated slightly with oil. (This oil must positively be 
removed when the bomb is in operation.) 

The pan may be cleaned by boiling in dilute hydro- 
chloric acid. Any further slag clinging to the pan may 
be fused with sodium carbonate. The fused mass dis- 
solves in hot water. 

Computation. — The data obtained during the run are 
used as follows: 

To the temperature in the calorimeter at firing and the 
maximum temperature is applied the correction for the 
errors on the thermometer, which are obtained from the 



FUEL ANALYSIS— HEATING VALUE. 105 

table of corrections supplied with the thermometer when 
it is standardized at the Bureau of Standards, The dif- 
ference between these corrected temperatures at maxi- 
mum and firing gives the true rise of temperature in the 
calorimeter, and to which must be added a cooling cor- 
rection, which is computed as follows : 

The change in temperature during the preliminary 
five minutes of reading, divided by the time (five minutes), 
gives the rate of change of temperature per minute, due 
to radiation to or from the calorimeter, and also any 
heating due to stirring, etc. Call this factor R u and in 
like manner the readings taken after the maximum tem- 
perature give R 2 . The rates of change of temperature 
give the existing conditions in the calorimeter at the 
start and at the finish of the run. The radiation to and 
from the calorimeter when the same is at room tempera- 
ture is o. Therefore: 

R1+0 ' 

X (time from firing temperature to room temperature) 

expresses the exchange of heat to and from the calorimeter 
in that part of the run from firing temperature to room 
temperature. In the same manner the expression 

o4-i? 2 
* X (time from room temp, to maximum temp.) 

gives a close approximation of the exchange of heat to 
and from the calorimeter during the latter part of the 
run. 

In the first factor above mentioned, as the time from 
firing temperature to room temperature is invariably 



106 GAS AND FUEL ANALYSIS 

close to one minute, the expression for cooling can be 
written as follows: 



— + 



f/? 2 . 1 * 

— X(time from room temp, to maximum temp.) . 



This latter quantity is either added to or subtracted 
from the above corrected rise in temperature, accordingly 
as the balance of heat radiation is to the surroundings or 
from the surroundings. This is at once determined from 
an inspection of the data. This rise of temperature, cor- 
rected for thermometer calibration errors, and with the 
cooling correction applied, is divided by the weight of 
fuel used, thus giving directly the rise in temperature per 
gram of fuel. 

This rise per gram, times the weight of water, plus 
" water equivalent " (see " standardization,") will give 
immediately the calories per gram of fuel, which is the 
result to be obtained. The result in calories per gram 
of fuel multiplied by the factor 1.8 gives B.T.U. per 
pound of fuel. 

Heavy Oils, Coke, Hard Coal, etc. 

The determination of the heat of combustion of heavy 
oils such as crude petroleum, and also of coke and ex- 
tremely hard coals, is best made by burning them mixed 

* If due to unusual atmospheric temperatures the run is made with 

temperatures all below or temperatures all above room temperature, 
I p 

X (time from firing temperature to maxi- 

2 

mum temperature) gives a close approximation for the cooling correc- 
tion. For an even closer approximation of the radiation correction, the 
Regnault-Pfaundler formula is recommended. 



then the expression 



1UW I 

[- 



FUEL ANALYSIS— HEATING VALUE. 107 

with a ready-burning combustible, such as a high-grade 
bituminous coal. This auxiliary combustible facilitates 
the complete combustion of the whole mixture in case of 
coke and hard coal, and with the heavy oil it acts as a 
holder and prevents rapid evaporation of the oil. 

A known weight of the auxiliary combustible should be 
placed at the bottom of the pan and the coke, coal or oil 
sprinkled over it. The auxiliary combustible should be 
dried and carefully standardized as to its rise in tempera- 
ture per gram in the calorimeter when the same is com- 
pletely burned. 

Weighing of Fuel Oils. — In the handling of fuel oil, 
the most suitable method of preventing evaporation in 
weighing the sample is to hold it in a small weighing bottle 
with a dropper arranged in the stopper for the purpose of 
conveying the liquid fuel to the sample of standard com- 
bustible in the fuel pan; and after a few drops have been 
placed here, the stopper is put again in the weighing 
bottle and the whole is reweighed. The difference 
between this weight and the weight previous to the taking 
out of the sample gives the net weight of fuel oil in the 
bomb. The upper half of the bomb should be imme- 
diately placed in position to prevent as much as possible 
the vaporization of the sample. 

Light Fuel Oils, Gasoline, Alcohol, etc. 

Because of the rapid evaporation of the lighter fuel oils 
it is not advisable to pour it directly into the fuel pan. 
Small gelatine capsules can be obtained which may be 
filled with ignited asbestos into which the light oils may 
be poured and absorbed by the asbestos. The filled 



108 CAS AND FUEL ANALYSIS. 

capsule is sealed, placed in the fuel pan and burned in 
the usual manner, using iron wire for ignition. The dry 
weight of the capsule and asbestos must be known and 
after filling capsule with charge and sealing it, the weight 
of the whole is taken. Care should be used that no air 
bubbles are enclosed with the charge in the capsule, as 
the fuel will otherwise ignite with explosive violence. 

THERMOMETERS. 

The accuracy of the calorimeter depends largely on the 
accuracy of the thermometer used in connection with the 
same. A good grade calorimetric thermometer, gradu- 
ated in x^o or 5V of a degree, ranging from about 15 to 
28 C, is a desirable type. This thermometer should have 
a Bureau of Standards calibration certificate. 

A Beckman type of thermometer with Bureau of Stand- 
ards certificate is satisfactory. 

STANDARDIZATION OF CALORIMETER. 

In the measurement of the heat of combustion of a fuel 
or a combustible in a bomb calorimeter, the immersed 
parts of the calorimeter including the bomb, can, stirrer, 
etc., are carried through the same rise in temperature as 
the water. The amount of heat absorbed by these im- 
mersed parts for one degree rise in temperature is known 
as the " Water Equivalent " factor of the apparatus. 

A bomb calorimeter when operated properly will give 
the true heat value of a given combustible if as a water 
equivalent factor we use that obtained from the weights 
and specific heats of the immersed parts, i.e., the sum of 
the products of the weight of each part times its specific 



FUEL ANALYSIS-HEATING VALUE. iog 

heat. The work of such physicists as Berthelot and 
Mahler has conclusively proven that this above method is 
correct. It is sometimes desirable to check this value by 
burning a combustible of known calorific value. Extreme 
care should be taken that such standardizing substances 
should be of ioo per cent purity and absolutely free from 
chemically or physically combined water. 

The value of such a standard substance in calories per 
gram is divided by the rise in temperature in the calor- 
imeter per gram of sample, and the result is the water 
plus the water equivalent of the apparatus. The water 
being known, the water equivalent is thus determined. 

With a combustible of absolute purity this determina- 
tion will check the value of the water equivalent as figured 
from the weights and specific heat of the material included 
in the immersed parts of the calorimeter. 

The chemically pure cane sugar, benzoic acid and 
naphthaline obtained at the Bureau of Standards, Wash- 
ington, D. C, are the only suitable materials to be used 
for the purpose of standardization of bomb calorimeters. 
These materials are prepared by the Bureau specifically 
for laboratories and users of combustion apparatus. The 
sample as received from the Bureau is in a finely divided 
condition suitable to be used for the work of standardiza- 
tion. With naphthaline, the sample should be briquetted 
or fused into a solid mass. 

To standardize the calorimeter with one of the above 
materials, the bomb, fuel pan and fuse wires are prepared 
in the same manner as in the testing of a fuel, except that 
the fuse wire should be of iron instead of platinum. The 
iron wire at the point where it touches the combustible 
should be wound in a narrow helix. The pan should be 



no GAS AND FUEL ANALYSIS. 

about three-quarters filled with a known weight of the 
standard, substance used, the iron fuse wire resting on its 
surface. One or two flakes of chemically pure naphthaline 
should be sprinkled on the coil where it is in contact with 
the material when cane sugar is used. These small pieces 
of naphthaline act as an igniter. For different diameters 
of iron fuse wire it will be necessary to change somewhat 
the resistance placed in series with the same. With wire 
about three- or four-thousandths of an inch in diameter, 
two ioo-watt lamps should be placed in the firing circuit 
in parallel and in series with the iron fuse wire. Wires 
larger than this latter diameter should have three or four 
lamps in parallel according to the size of the same. 

In making a run the weight of combustible is recorded, 
the weight of the naphthaline used as an igniter, and the 
weight of the iron fuse wire burned. The latter quantity 
is obtained by weighing the entire piece of fuse wire orig- 
inally connected in the bomb, and subtracting from that 
weight of the unburned ends if any are found after the run. 
The following corrections must be made: 

i. The heat generated by the burning of the small 
quantity of naphthaline used as an igniter. 

2 . The heat generated by the burning of the iron fuse wire. 

3. The heat input of the electrical current used in 
bringing the fuse wire to incandescence. 

4. The heat of formation of nitric acid. 

With reference to the above : 

The heat of combustion of naphthaline is 9610 calories 
per gram. 

The heat of combustion of iron wire is 1600 calories 
per gram. 






FUEL ANALYSIS— HEATING VALUE. in 

The correction for electrical input can be best deter- 
mined by a blank run in which wire of the same diameter 
as that to be used in the test is burned in the bomb without 
the presence of a charge of combustible. This blank run 
is made with the temperature in the calorimeter bucket 
exactly the same as the surrounding conditions, in order 
that a cooling correction will be avoided. When the tem- 
peratures within and without the calorimeter are exactly 
equalized, the current is turned on and the iron wire 
ignited. The current is turned on for an exact period 
of time, i.e., either of one or two seconds' duration. This 
continuation of the flow of current should be exactly 
duplicated when the standardization run is being made 
and the standard combustible is being burned. From 
the total calories developed in the blank run should be 
subtracted the heat developed due to the burning of the 
known weight of iron wire. The remainder gives the 
amount due to the flow of current. 

In supplying the correction for the formation of nitric 
acid, an arbitrary correction of about ten calories is satis- 
factory. 

These above corrections are all sub tractive and are de- 
ducted from the results as obtained from the calorimeter test. 

The mean value for the heat of combustion of cane sugar 
is 3950 calories per gram. The heat of combustion of 
benzoic acid is 6320 calories per gram. 

For further detailed information regarding the standard- 
ization of bomb calorimeters, Circular No. 11 of the 
Bureau of Standards is recommended. 

The water equivalent factor of the Emerson Fuel 
Calorimeter, as computed from the immersed parts and 
their specific heats, is furnished with the outfit. 



112 



GAS AND FUEL ANALYSIS. 



Specific heat of steel = 0.116; of nickel = 0.109; of 
brass = 0.094; of vulcanite = 0.331; of copper = 0.092; 
of platinum = 0.032. 

Heat of Combustion. 
Sample Run. 

November 20, 191 2. 
Sample No. 128 (air dried.) Run No. 2. 

Thermometer used, No. 2295. 

Weight of tube and coal = 7.9379 Room Temp. = 22 C. 

Weight of tube and coal = 7.071-] 



Weight of fuel .8666 gram 

Weight of water 1900 grams 

Readings of Thermometer. 



Time Temp. 

20.348 

1 20.352 

2 20.358 

3 20.362 

4 20.368 

5 20.376 Firing Temp. 
21.000 



Time 



Temp. 
22.600 



30 



30 



30 



30 



30 



Time 


Temp. 


IO 


23-194 


II 


23.182 


12 


23.174 


13 


23.166 


14 


23-I58 


15 


23-I50 



22.900 
23.100 

23.150 
23.194 

23.196 Max. Temp. 

23.196 

23.194 

/Calibration^ 
\ Correction / 

Temperature at firing = 20.3 76+ ( — .011) =20.365 

Temperature at max. =23.196+ (4- .002) =23.198 

Rise in temperature corrected for errors in thermometer =2.833 

Rate of change of temperature before firing = 0.0056 = ^1 

Rate of change of temperature after maximum temperature = 0.0088 = R 2 * 

(-.0056) , (+.0088) 

Total cooling corr. = X (1) H X (2.5) = .008 (additive) 

2 2 

Total corrected rise in temperature =2.841. 

Rise per gram of sample = 3. 2 78 

The water equivalent of bomb, calorimeter can, stirrer, etc.= 

Gram calories per gram of coal= (1900+490) X3. 278 = 7834 

British Thermal Units per pound of coal= 7834X1.8 = 14,100 



490 



Rate for last five minutes. 



FUEL ANALYSIS— HEATING VALUE. 1 13 

Berthier's Method. — Another method of direct deter- 
mination was proposed by Berthier in 1835.* It uses 
as a measure of the heating value the amount of lead 
which a fuel would reduce from the oxide; in other 
words it is proportional to the amount of oxygen ab- 
sorbed. 

The method is as follows f : Mix one gram of the 
finely powdered dry coal with 60 grams of oxide of lead 
(litharge) and 10 grams of ground glass. This mixing 
can be done with a palette-knife on a sheet of glazed 
paper; the mixture is transferred to a fire-clay crucible 
(Battersea C size), covered with salt, the crucible covered 
and heated to redness in a hot gas-furnace — or the hottest 
part of the boiler-furnace — for 15-20 minutes. After 
cooling, the crucible is broken and the lead button care- 
fully cleaned and weighed. Multiply the weight of the 
lead button obtained by 268.3 calories (or 483 B. T. U.) 
and divide the product by the weight of coal taken. The 
result is the number of calories per gram or B. T. U. per 
pound. One gram of lead is theoretically equivalent to 
234 calories (C) ; owing to the hydrogen present this factor 
gives results about 2 per cent too low. The results ob- 
tained by the author using " horn-pan " scales in one case 
by this method were within 2.8 per cent of those yielded 
by the bomb calorimeter, which are as close as those 
obtained by any calorimeter save Parr's. The method 
would seem worthy of more attention than it has re- 
ceived. 

* Dingler's Polytechnisches Journal, 58, 391. 

t Noyes, McTaggart and Craver, J. Am. Chem. Soc, 17, 847 (1895). 



114 GAS AND FUEL ANALYSIS. 

b. Determination of Heating Value by Calculation. 

The method of determination of the heating value first 
described, though exact, has the disadvantages that the 
apparatus is costly and the compressed oxygen is not 
easily obtained. To obviate these, it has been sought to 
obtain the heating value by calculation from the chem- 
ical analysis, the heating value of the constituents being 
known. This has the disadvantage that we have no 
absolute knowledge — nay, not even an approximate idea — 
as to how the carbon, hydrogen, water, and sulphur exist 
in the coal, so that any formula must of necessity be quite 
removed from the truth. Dulong was the first to propose 
the method by calculations, and his formula as modified 
by Bunte * is 

8080c + 28800 (h --) + 2500s -6002^ 
100 

c y h, o } s and w representing the percentages of carbon, 
hydrogen, oxygen, sulphur and water in the coal. It gives 
results varying from +2.8 to -3.7 per cent; it would 
scarcely seem that the sulphur would be worth consider- 
ing unless high, 1 per cent affecting the result but 0.3 
per cent. The hydrogen is considered as burned to 
aqueous vapor. 

The results obtained by these formulas for anthracite 
coal are as a rule considerably too low. 

The heating value can also be determined from the 
proximate analysis — the percentage of fixed carbon and 

* Jour, fur Gasbeleuchtung, 34, 21-26 and 41-47. 



FUEL ANALYSIS—HEATING VALUE. 



"5 



volatile matter; this has been well shown by Maujer.* 
The chart, Fig. 23, was constructed from over 300 
analyses of representative coal made by the Bureau of 
Mines; the curve is most accurate for coals having from 
64-90 per cent of fixed carbon in the combustible matter; 
where this is less than 64 per cent the error may be as 
much as 7 per cent 



To determine the heating value of 



15, 
15, 
15. 
15, 
15, 
© 15, 
§15, 

m 

M 15. 

« u, 

1±, 

Mj 

1±, 

Fig. 



,<uu 




















































































































































Ill 1 








,b!Ai 




































































































































- 




























J 




























bOO 




































^ 
































































,m 
































































































































\ 








,300 










































































,200 


































\ 


































































\: 








,100 




























































I 














































/ 








































J 




































,000 














































































































































































,900 


































































































































■* 










,800 


' / 






















































-■ \ 




1 1/ 










































1 l\l L 


,700 


| / 






































r 











/ 








































600 






_i 1 / 






























M ' 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ! ■ ' 




. \ 








/ 










































,500 






/ 


















































































,400 










.300 








I / i 




200 




/ 






/ 




,100 


- 


/ 1 






/ 










/I 1 1 1 1 I 1 1 1 1 1 II 1 I 1 1 1 1 II I II 1 1 1 1 1 1 1 1 1 II 1 1 1 1 1 II 1 II 1 







70 75 

Per Cent 



100 



23. — Chart for Determining Heat Value of Combustible 
with Different Percentages of Fixed Carbon. 



the coal from the chart, the percentage of fixed carbon is 
divided by the sum of the fixed carbon and of the volatile 
combustible matter and multiplied by 100; this gives the 
percentage of fixed carbon in the combustible matter. Let 
us suppose a coal of this composition; moisture, 5.12, 



* Power, 37, 836 (1913), also in "Fuel Economy and C0 2 Recorders," 
(1916), pp. 45-47- A similar curve is given by Kowalke, Power, 35, 559 
(1912). 



n6 GAS AND FUEL ANALYSIS. 

volatile combustible matter 27.25, fixed carbon 53.38, 
and ash 14.25 per cent. The sum of the volatile matter 
and fixed carbon is (27.25 + 53.38) = 80.63 divided into the 

fixed carbon n ' X 100 = 66.2 per cent. 
80.63 r 

That is, there are 66:2 per cent fixed carbon in the total 
combustible matter; using this as an abscissa (horizontal 
distance), in Fig. 23 we find 15,400 B. T. U. as the 
corresponding ordinate; this is the heating value of the 
combustible matter in the coal; since by the above cal- 
culation but 80.63 P er cent °f ^e coal is combustible, 
the heating value of the coal is 80.63X15,400 or 12,420 
B. T. U. 

CALORIFIC POWER OF GASEOUS FUEL. 

a. Direct Determination. 

Perhaps the best apparatus for the determination of 
the heating value of gases is the Junkers calorimeter, 
Figs. 24 and 25. The following description is taken 
from an article by Kuhne in the Journal of the Society 
ot Chemical Industry, vol. 14, p. 631.* As will be 
seen from Fig. 24, this consists of a combustion-chamber, 
28, surrounded by a water-jacket, 15 and 16, this being 
traversed by a great many tubes. To prevent loss by 
radiation this water-jacket is surrounded by a closed 
annular air-space, 13, in which the air cannot circulate. 
The whole apparatus is constructed of copper as thin as 
is compatible with strength. The water enters the jacket 

* See also Industrial Gas Calorimetry, Tech. Paper No. 36, Bur. 
Standards; Standard Methods of Gas Testing, Circular No. 48, Bur. 
Standards. 



FUEL ANALYSIS— HEATING VALUE. 



117 



at 1, passes down through 3, 6, and 7, and leaves it at 21, 
while the hot combustion-gases enter at 30 and pass 
down, leaving at 31. There is therefore not only a very 




QoSa 



Fig. 24. — Junkers Gas-calorimeter (Section). 

large surface of thin copper between the gases and the 
water, but the two move in opposite directions, during 
which process all the heat generated by the flame is 
transferred to the water, and the waste gases leave the 
apparatus approximately at atmospheric temperature. 
The gas to be burned is first passed through a meter, 



n8 



GAS AND FUEL ANALYSIS. 



Fig. 25, and then, to insure constant pressure, through 
a pressure regulator. The source of heat in relation to 
the unit of heat is thus rendered stationary; and in 







Fig. 25. — Junkers Gas-calorimeter. 

order to make the absorbing quantity of heat also 
stationary, two overflows are provided at the calo- 
rimeter, making the head of water and overflow con- 
stant. The temperatures of the water entering and 
leaving the apparatus can be read by 12 and 43; as 
shown before, the quantities of heat and water passed 



FUEL ANALYSIS— HEATIXG VALUE. 



119 



through the apparatus are constant. As soon as the 
flame is lighted, 43 will rise to a certain point and will 
remain nearly constant. 

Manipulation. — The calorimeter is placed as shown 
in Fig. 25, so that one operator can simultaneously 
observe the two thermometers of the entering and 
escaping water, the index of the gas-meter, and the 
measuring-glasses. 

No draft of air must be permitted to strike the ex- 
haust of the spent gas. 

The w T ater-supply tube zv is connected with the 
nipple a in the centre of the upper container; the 
other nipple, b, is provided with a waste-tube to carry 
away the overflow, which latter must be kept running 
while the readings are taken. 

The nipple c through which the heated water leaves 
the calorimeter is connected by a rubber tube with 
the large graduate, d empties the condensed water 
into the small graduate. 

The thermometers being held in position by rubber 
stoppers and the water turned on by e until it dis» 
charges at c> no water must issue from d or from 39, 
Fig. 24, as this would indicate a leak in the calorim- 
eter. 

The cock e is now set to allow about two liters of 
water to pass in a minute and a half, and the gas 
issuing from the burner ignited. Sufficient time is 
allowed until the temperature of the inlet-water 
becomes constant and the outlet approximately so; 
the temperature of the inlet-water is noted, the read- 
ing of the gas-meter taken, and at this same time the 
outlet-tube changed from the funnel to the graduate. 



120 GAS AND FUEL ANALYSIS, 

Ten successive readings of the outflowing water are 
taken while the graduate (2-liter) is being filled and 
the gas shut off. 

A better procedure is to allow the water to run into 
tared 8-liter bottles, three being used for a test, and 
weighing the water. The thermometer in the outlet 
can then be read every half-minute. 

Example. — Temp, of incoming water, 17. 2° 
" " outgoing M 43.8° 

Increase, 26. 6° 

Gas burned, 0.35 cu. ft. 

liters water X increase of temp. 2 X 26.6 

Heat = — — — = 

cu. ft. gas 0.35 

= 152 3C. 

From burning one cubic foot of gas 27.25 cc. of 
water were condensed. This gives off on an average 
0.6 C. per cc. 

27.25 xo.6 = i6.3 C; 152,3 — 16.3 = 136 C. per cubic 
foot; 136x3. 96823 = 540 B.T.U. 

NOTES. — After setting up the apparatus the first 
thing to be done is to turn on the water — (not the gas). 
Similarly, the water should be shut off last. All con- 
nections and the meter should be tested for leaks be- 
fore each test. The water level in the meter should 
be checked daily. Slight drafts caused by moving 
suddenly near the apparatus will vary outlet readings 
and vitiate the test. The instrument should not be 
set up near a window or heating apparatus where 
radiant heat might affect the readings. 

If 0.2 cu. ft. of gas are burned, then an error of 
o. 1 ° F. in temperature of water means an error of 
4 B.T.U.; an error of 0.01 lb. water, 0.9 B.T.U.; 
i°F. in gas temperature, 1.8 B.T.U. ; 0.1 inch (barom- 



FUEL ANALYSIS— HEATING VALUE. 121 

eter), 2 B.T.U.; i inch water pressure of gas, 1.5 
B.T.U.* 

The calorific power obtained without subtracting 
the heat given off by the condensation of the water 
represents the total heating value of the gas. This is 
the heat given off when the gas is used for heating 
water or in any operation where the products of 
combustion pass off below ioo° C, and is the one 
which should be reported. It should, however, be 
corrected,! as shown on page 124, to the legal cubic 
foot, that is, measured at 30 inches barometric pressure, 
and 6o° F. saturated with moisture. 

The net heating value represents the conditions in 
which by far the greater quantity of gas is consumed, 
for cooking, heating and gas engines. 

The apparatus has been tested for three months 
in the German Physical Technical Institute with hy- 
drogen, with but a deviation of 0.3 per cent from 
Thomson's value. This value may vary nearly that 
amount from the real value owing to the method 
which he employed. 

b. By Calculation. 

Oftentimes it may be impracticable to determine 
the heating value of gases directly; in such cases 
recourse must be had to the calculation of its calorific 
power from volumetric analysis of the gas. 

* Rept. Joint Committee on Calorimetry Public Service Commission 
and Gas Corporations in the Second Public Service District of New 
York State (1910), p. 81. 

f A difference of i° C. or of 3 mm. pressure makes a change of 0.3 
per cent in the volume. Pfeiffe, J. Gasbeleucht., 50, 67 (1870). 



122 GAS AND FUEL ANALYSIS. 

To this end multiply the percentage of each con- 
stituent by its number as given in Table IV, and the 
sum of the products will represent the British Thermal 
Units evolved by the combustion of one cubic foot of 
the gas.* It is assumed that the temperature of the 
gas burned and the air for combustion is 6o° F., and 
that of the escaping gases is 328 F., that correspond- 
ing to the temperature of steam at 100 pounds abso- 
lute pressure. 

As has been already stated, column 3 in Table IV 
is based upon the assumption that the gas, and air for 
its combustion, enter at 6o° F., and the products 
of combustion leave at 328°F. ; in column 4 it is 
assumed that the entering temperature of both gas 
and air is 32 F., and the combustion-gases are cooled 
to 32 F. In case these conditions are varied, the 
amount of heat which the gas and air bring in must be 
determined; this is found in the usual way by multi- 
plying the proportionate parts of 1 cubic foot, as 
shown by the analysis, by the specific heat of the gas, 
and this by the rise in temperature (difference between 
observed temperature and 32 F.). The quantity of 
air necessary for combustion is found by multiplying 
the percentage composition cf the gas by the number 
of cubic feet necessary for the combustion of each 
constituent. 

An example will serve to make this clear. The 
analysis of Boston gas is as follows: f 

CO a "Illuminatus." O CO CH 4 H N 

2.9 15.O O.O 25.3 25.9 27.9 3.0 

* H. L. Payne, Jour. Analytical and Applied Chem., 7, 230. 
f Jenkins, Annual Report Inspector of Gas Meters and Illuminat- 
ing Gas, 1896, p. 11. 



FUEL ANALYSIS— HEATING VALUE. 123 

Or in one cubic foot there are 

.029 C0 3 259 CH 4 

.150 " illuminants " 279 H 

.253 CO 030 N 

Let us assume that the gases, instead of passing 
out at a temperature of 32 8° F., leave at the same 
temperature as that of the chimney-gases, p. 29, 250 
C or 482 F. 

The calculation of the heat carried away is similar 
to that there given. 
0.15 cu. ft. of " illuminants M produces, Table III, 

0.3 cu. ft. C0 2 and 0.3 cu. ft. steam; 
0.253 cu. ft. of carbonic oxide produces .253 cu. ft. 

C0 2 ; 
0.259 cu. ft. methane produces 0.259 cu - ft- CO a and 

.518 cu ft. steam; 
0.279 cu. ft. hydrogen produces .279 cu. ft. steam. 

From the combustion of the gas there results .812 
cu. ft. C0 2 , 1.097 cu. ft. steam, and 5.90 X 79.08 or 
4.665 cu. ft. N. 

The quantity of heat they carry off is as follows: 

Vol. Vol. Sp. Ht. Rise. B.T.U. 

C0 2 812 X .027 x 450= 9-9 

N 4.66 X .019 X 450= 39-9 

Excess of air.. 1.2 X .019 X 450= 10.2 

Steam 1-097 X .0502 X 1229 = 6y.y 



Total heat lost = 127.7 

The loss due to the steam is found by multiplying 
the weight of steam found by the " Total Heat of 



124. GAS AND FUEL ANALYSIS. 

Steam," as found from Steam Tables.* The tables, 
however, do not extend beyond 428 F. ; it can be 
calculated by the formula 

Total heat = X = 1091.7 -f- 0.305^ — 32). 

One cubic foot of hydrogen when burned yields • 
.0502 lbs. of water. 

The heat generated by the combustion of the gas is 
found by multiplying its volume by its calorific power, 
Table IV. 

11 Illuminants" o. 15 X 2000.0 = 300.0 B.T.U. 

CO 0253X 341.2= 86.3 

CH 4 0.259 x 1065.4 = 276.0 

H 0.279X 345-4= 9 6 -3 

Heat generated by the gas 758.6 B.T.U. 

Total heat lost (p. 109) l2 7-7 

630.9 B.T.U. 
This figure, 630.9 B.T.U., represents the heating 
power of one cubic foot of the gas measured at 62 F., 
and is consequently too small ; its heating value at 
32 F. is represented by 

492 + 3 Q x g 309j or669#I B.T.U. 

The above calculation, like all giv'ng accurate results, 
is somewhat tedious; a shorter and less correct one is as 
follows: Divide the figures found in the last column of 
Table IV of the Appendix by 100, the result gives the 
heating value of these gases in B.T.U. per cubic centi- 

* Pcabody's Steam Tables. 



FUEL ANALYSIS— HEATING VALUE. 125 

meter* According to the volumetric analysis of the 
gas there are in 100 cc. the following: 

15.0 cc. illuminants, 
25.3 cc. carbonic oxide, 
25.9 cc. methane, 
27.9 cc. hydrogen. 
The heating value is 

15.0X20.0 =300.0 B.T.U. 
25-3 X 3-4i= 86.3 
25.9X10.65 =276.0 
27-9X 345= 96.3 



758.6 B.T.U. 

the same as the gross heating value obtained by the other 
method. No correction is applied for the heat lost. 

* Method followed in Prof. Paper, No. 48, U. S. Geol. Survey, 
Part III, p. 1005. 



APPENDIX. 



TABLE I. 

TABLE SHOWING THE TENSION OF AQUEOUS VAPOR AND ALSO THE 
WEIGHT IN GRAMS CONTAINED IN A CUBIC METER OF AIR 
WHEN SATURATED. 

From 5 to 30 C. 



Temp. 


Tension, 
mm. 


Grams. 


Temp. 


Tension, 
mm. 


Grams. 


Temp. 


Tension, 
mm. 


Grams. 


5 


6.5 


6.8 


14 


II. 9 


I2.0 


23 


20.9 


20.4 


6 


7.0 


7-3 


15 


12.7 


12.8 


24 


22.2 


21.5 


7 


7-5 


7-7 


16 


13-5 


13.6 


25 


23-6 


22.9 


8 


8.0 


8.1 


17 


14.4 


14-5 


26 


25.O 


24.2 


9 


8.5 


8.8 


18 


15.4 


I5-I 


27 


26.5 


25.6 


10 


9.1 


9.4 


19 


16.3 


16.2 


28 


28.1 


27.O 


11 


9.8 


10. 


20 


17.4 


17.2 


29 


29.8 


28.6 


12 


10.4 


10.6 


21 


18.5 


18.2 


30 


31-5 


29.2 


13 


11. 1 


II. 3 


22 


19.7 


19-3 












TABLE II. 

" VOLUMETRIC " SPECIFIC HEATS OF GASES.* 



Air 0.019 

Carbon dioxide 0.027 

Carbonic oxide 0.019 

Hydrogen 0.019 



" Illuminants " 0.040 

Methane 0.027 

Nitrogen .. 0.019 

Oxygen 0.019 



The " volumetric " specific heat is the quantity of heat neces- 
sary to raise the temperature of one cubic foot of gas from 32 F. 
to 33 F. 



* H. L. Payne, Jour, Anal, and Applied Ckem., 7, 233. 

127 



128 



APPENDIX. 



TABLE III. 

THE VOLUME OF OXYGEN AND AIR NECESSARY TO BURN ONE CUBIC 
FOOT OF CERTAIN GASES, TOGETHER WITH THE VOLUME OF THE 
PRODUCTS OF COMBUSTION. 



Name. 



Hydrogen . 
Carbonic oxide 

Methane 

Ethane 

Propane 

Butane 

Pentane 

Hexane 

Ethylenef . . • 
Propylene J. . 

Benzene§ 

Acetylene. . . . 



Formula. 


Volume 


Volume* 


Volume 


Volume 


of 


of 


of 


of Carbon 




Oxygen. 


Air. 


Steam. 


Dioxide. 


H 2 


o.S 


2-39 


1 


O 


CO 





5 


2 


39 


O 


1 


CH 4 


2 





9 


56 


2 


1 


C2H6 


3 


5 


16 


73 


3 


2 


C3H8 


5 





23 


90 


4 


3 


C4H10 


6 


5 


3i 


07 


5 


4 


C5H12 


8 





38 


24 


6 


5 


CeHi4 


9 


5 


45 


4i 


7 


6 


C2H4 


3 





14 


34 


2 


2 


C3H6 


4 


5 


21 


5i 


3 


3 


CeHe 


7 


5 


35 


«5 


3 


6 


C2H2 


2 


5 


11 


95 


1 


2 



Ignition 

Point 

Deg. F. 



1085 || 
1 200 1 1 
1230 
1 140 
1015 



1400 
1010 II 

940 

'788 II 



* Air being 20.92% by volume, 4.78 vols, contain 1 vol. of oxygen. 

t The chief constituent of " illuminants," new name " ethene." 

X New name " propene." 

§ Often called benzol, not to be confounded with benzine. 

|| Dixon & Coward, Proc. Chem., Soc, 26, 67. 

TABLE IV. 

SPECIFIC HEATS OF VARIOUS OILS USED AS FUEL. 

Alcohol, absolute o . 700 

Benzol o . 430 

Ether o . 503 

Gasoline { 

I 0.700 

Kerosene o . 500 

Machine oil o . 400 

Paraffin oil o . 5 20 

Paraffin solid o . 600 

Crude oils, Pa o . 500 

Crude oils, Cal o. 398 

Crude oils, Russia o. 435 

LATENT HEAT OF VAPORIZATION * B.T.U. PER POUND. 

Gasoline 130 

Gas oil 200-250 

*Cross, " Oil and Gas News," 2, 13 (1917). 






TABLES. 



129 



TABLE V. 

CALORIFIC POWER OF VARIOUS GASES * IN BRITISH THERMAL UNITS PER 

CUBIC FOOT. 



Name. 


Symbol. 


6o° initial. 
328 final. § 


32 initial. 
32 final. 


Hydrogen 


H 

CO 

CH 4 

cVh b 

C3H8 

C4H10 

C*Hia 

CeHi4 

C2H4 

C3H6 

CeH e 

C2H2 


263.2 

306.9 

853-0 

I 700 . O 


345-4 

341.2 

1065.0 

2000.0 


Carbonic oxide 

Methane 


Illuminantsf 


Ethane.. 


1861.0 


Propane 


2657.0 
3441.0 
4255.0 
5017.0 
1674.0 
2509.0 
4012.0 
I477.0 


Butane. « 


Pentane 


Hexanet 


Ethylene 


Propylene 


Benzene 


Acetylene 







* H. L. Payne, loc. cit. 

f Where the "illuminants" are derived chiefly from the decom- 
position of mineral oil. 

I The chief constituent of the "gasolene'' used in the gas machines 
for carburctting air. 

§ The temperature of steam at 100 lbs. absolute pressure. 



TABLE VI. 

CALORIFIC POWER OF VARIOUS LIQUIDS IN BRITISH THERMAL UNITS PER 

POUND. 



Name. 



B. T. U. 



Pounds of Air for 
Combustion. 



Crude petroleum, Lima, Ohio . . . 
Crude petroleum, Oil Creek, Pa . 
Crude petroleum, heavy, W. Va. 

63 Be. gasolene 

114 F. flash kerosene 

150 fire- test kerosene 

Mineral sperm 

Ethyl alcohol, 95 per cent 

Methyl alcohol 

Denatured alcohol 

Benzole 



20,890 

21,600 

18,180 
19,162-20,448 
18,643-19,892 

18,290 

20,065 

10,504 

9,565 
10,512-11,616 

17,260-18,000 



14.96* 
14.89* 



8.13* 



* Bull. 43 Bureau of Mines, 191 2, pp. 18-21. " Fuel Values of Gaso- 
lene and Denatured Alcohol in Internal Combustion Engines." 



13° 



APPENDIX. 



TABLE VII. 

CALORIFIC POWER OF CERTAIN SOLID FUELS IN BRITISH THERMAL UNITS 
PER POUND, FIGURED ON THE PURE DRY COMBUSTIBLE. 

Anthracite 13,740-15,620 

Bituminous coal: 

Cumberland 16,320 

Georges Creek 15,140 

Pocahontas 15,700 

West Virginia 13,700 

Brown coal 9,060-14,240 

Coke 13,880-14,560 

Peat.' 7,400-10,625 

Tanbark 6,100 

Wheat straw 10,380 

Wood, hard 8,500 

Wood, pine 9,150 



TABLE VIII. 

SHOWING THE MOLECULAR WEIGHT, THE WEIGHT OF A LITER AND SPECIFIC 
GRAVITY, REFERRED TO AIR, OF CERTAIN GASES AT 0° C. AND 760 MM. 



Name of Gas. 


Molecular 
Weight, 
22.4 L. 


Weight, 
Grams. 


Specific 
Gravity. 


Carbonic oxide 


28 

44 
2 
16 
28 
32 

28.95 
18 


I. 251 
I.966 
O.0896 

0.7I5 
1-255 
I.430 
I.294 
O.803 


O.967 

I-5I9 
O.069 
O.553 


Carbon dioxide 


Hydrogen 


Methane 


Nitrogen 


O.970 


Oxygen 


1. 105 
I. OOO 


Air 


Steam 


O.621 







13.14 cu. ft. air at 62 F., and 30 in., weighs 1 lb. 
12.40 cu. ft. air at 32 F., and 30 in., weighs 1 lb. 
359 cu. ft. of a gas is a pound mol. (molecular weight in pounds). 






TABLES. 



131 



TABLE IX. 

SOLUBILITY OF VARIOUS GASES IN WATER. 

One volume of water at 20 C. absorbs the following volumes of gas 
reduced to o° C, and 760 mm. pressure. 



Name of Gas. 


Symbol. 


Volumes. 


Carbonic oxide 

Carbon dioxide 


CO 

ca 

H 2 
CH 4 
N 2 
0, 

C0H4 


O.023 
O.goi 
0.019 
0-035 
0.014 
O.028 
0.017 
O.150 


Hydrogen 

Methane 

Nitrogen 

Oxygen 

Air 


Ethylene 





TABLE X. 

MELTING-POINTS OF VARIOUS METALS AND SALTS, FOR USE WITH 
APFARATUS FIG. II. 



Alphabetically. 

Aluminium 6 s 



8°C. 



Antimony 630 

fBarium chloride 950 

Bismuth 270 

Calcium fluoride 902 

Cadmium 302 

f Cadmium chloride 541 

Copper 1083 

Lead 327 

f Potassium bromide. . . . 740 

fPotassium chloride .... 780 

fSodium bromide 748 

fSodium carbonate 853 

Tin 232 

Zinc 419 



By Temperatures. 

Tin 232°C* 

Bismuth 270* 

Cadmium 302* 

Lead 327* 

Zinc 419* 

Cadmium chloride 541 1 

Antimony 630* 

Aluminium 658* 

Potassium bromide 740* 

Sodium bromide 748* 

Potassium chloride 780* 

Sodium carbonate 853* 

Calcium fluoride 902 § 

Barium chloride 950* 

Copper 1083* 



* Burgess-Le Chatelier, Measurement of High Temperatures, 191 2. 
t These salts must be dried at 105 C. to a constant weight. 
t Carnelley, Melting- and Boiling-point Tables. 
§ Meyer, Riddle and Lamb, Ber. d. deut. Chem. Gesellsch., 27, 
3140 (1894). 



13* 



APPENDIX. 
TABLE XI. 



GIVING THE NUMBER OF TIMES THE THEORETICAL QUANTITY OF 
AIR SUPPLIED, WITH VARIOUS GAS ANALYSES.* 



C cV 


N = 7 Q. 


N = 80. 


N = 81. 


N = 82. 


C0 2 +0+CO = 2i 


CO a ~hO+CO = 2o. 


CO a +0+CO = i9. 


C0 2 +0+CO = i8. 


21 


1 .00 








20 


1.05 


I. 


00 


.... 


.... 


19 


1 . IO 


I. 


05 


I .OO 


.... 


18 


1. 17 


I. 


10 


I.05 


I. OO 


17 


1.23 


I 


16 


I.IO 


I.05 


16 


I-3I 


I 


23 


1. 16 


I.IO 


15 


I.40 


I 


3i 


1.23 


1. 16 


14 


I.50 


I 


39 


1.30 


1.22 


13 


1. 61 


I 


49 


1-39 


1.30 


12 


1.75 


I 


60 


1.48 


1.38 


II 


1. 91 


I 


73 


1-59 


1.47 


IO 


2.IO 


I 


89 


1.72 


1.58 


9 


2-33 


2 


07 


1.87 


1.70 


8 


2.62 


2 


29 


2.04 


1.85 


7 


3.00 


2 


57 


2.26 


2.02 


6 


3 -5o 


2 


.92 


2.52 


2.23 


5 


4.20 


3 


•39 


2.86 


2.48 


4 


5.25 


4 


.05 


3-30 


2.79 


3 


7.00 


5 


.00 


3-89 


3- 20 


2 


10.50 


6 


•53 


4.76 


3-76 


1 


21 .00 


9 


•43 


6.10 


4-54 



* Coxe, Proc. N. E. Cotton Manufacturers' Assoc, 1895. 



TABLE XII. 

COMPARISON OF METRIC AND ENGLISH SYSTEMS. 

i cubic inch =16.39 c - c - 

1 cubic foot =28.315 liters. 

1 cubic meter =3532 cu. ft. 
1 Imperial gallon = 4. 543 liters. 



1 lb. avoirdupois = 45 3. 5 93 grams. 

1 calorie = 3.969 B.T.U. (Rontgen). 



COAL AND FUEL OIL SPECIFICATIONS. 133 

COAL AND FUEL OIL SPECIFICATIONS. 

COAL SPECIFICATIONS.* 

The following, from Bulletin 339, U. S. Geological Survey (1908), by 
D. T. Randall, will give an idea of some coal specifications: 

SPECIFICATIONS FOR THE U. S. GOVERNMENT FUEL 
SUPPLY AS APPROVED BY THE NATIONAL ADVISORY 
BOARD ON FUELS AND STRUCTURAL MATERIALS, 
MARCH, 1907. 

Specifications and Proposals for Supplying Coal. 

United States 

, 190 

PROPOSAL. 

Sealed proposals will be received at this office until 2 o'clock p.m., 

190. ., for supplying coal to the United States building 

at as follows: 



The quantity of coal stated above is based upon the previous annual 
consumption, and proposals must be made upon the basis of a delivery 
of 10 per cent more or less than this amount, subject to the actual 
requirements of the service. 

Proposals must be made on this form, and include all expenses 
incident to the delivery and stowage of the coal, which must be delivered 
in such quantities and at such times within the fiscal year ending 
June 30, 190. ., as may be required. 

Proposals must be accompanied by a deposit (certified check, when 

practicable, in favor of ) amounting to 10 per cent 

of the aggregate amount of the bid submitted, as a guaranty that it is 
bona fide. Deposits will be returned to unsuccessful bidders imme- 
diately after award has been made, but the deposit of the successful 
bidder will be retained until after the coal shall have been delivered 
and final settlement made therefor, as security for the faithful per- 
formance of the terms of the contract, with the understanding that 
the whole or a part thereof may be used to liquidate the value of any 

* See also Bulletin 63, Bureau of Mines (1913), Sampling Coal De- 
liveries. 



134 APPENDIX. 

deficiencies in quality or delivery that may arise under the terms of 
the contract. 

When the amount of the contract exceeds $10,000, a bond may be 
executed in the sum of 25 per cent of the contract amount, and in this 
case the deposit or certified check submitted with the proposal will 
be returned after approval of the bond. 

The bids will be opened in the presence of the bidders, their repre- 
sentatives, or such of them as may attend, at the time and place above 
specified. 

In determining the award of the contract, consideration will be 
given to the quality of the coal offered by the bidder, as well as the 
price per ton, and should it appear to the best interests of the Govern- 
ment to award the contract for supplying coal at a price higher than 
that named in lower bid or bids received, the award will be so made. 

The right to reject any or all bids and to waive defects is exp/essly 
reserved by the Government. 

DESCRIPTION OF COAL DESIRED.* 

Bids are desired on coal described as follows: 



Coals containing more than the following percentages, based upon 
dry coal, will not be considered: 

Ash per cent 

Volatile matter per cent 

Sulphur per cent 

Dust and fine coal as delivered at point of 

consumption f per cent 

DELIVERY 

The coal shall be delivered in such quantities and at such times as 
the Government may direct. 

In this connection it may be stated that all the available storage 
capacity of the coal bunkers will be placed at the disposal of the con- 
tractor to facilitate delivery of coal under favorable conditions. 

* This information will be given by the Government as may be determined 
by boiler and furnace equipment, operating conditions, and the local market, 
t All coal which will pass through a £-inch round-hole screen. 



COAL AND FUEL OIL SPECIFIC ATIOXS. 135 

After verbal or written notice has been given to deliver coal under 
this contract, a further notice may be served in writing upon the con- 
tractor to make delivery of the coal so ordered within twenty-four 
hours after receipt of said second notice. 

Should the contractor, for any reason, fail to comply with the second 
request, the Government will be at liberty to buy coal in the open 
market, and to charge against the contractor any excess in price of 
coal so purchased over the contract price. 

SAMPLING. 

Samples of the coal delivered will be taken by a representative of 
the Government. 

In all cases where it is practicable, the coal will be sampled at the 
time it is being delivered to the building. In case of small deliveries, 
it may be necessary to take these samples from the yards or bins. The 
sample taken will in no case be less than the total of 100 lbs., to be 
selected proportionally from the lumps and fine coal, in order that 
it will in every respect truly represent the quantity of coal under con- 
sideration. 

In order to minimize the loss in the original moisture content the 
gross sample will be pulverized as rapidly as possible until none of 
the fragments exceed one-half inch in diameter. The fine coal will 
then be mixed thoroughly and divided into four equal parts. Opposite 
quarters will be thrown out, and the remaining portions thoroughly 
mixed and again quartered, throwing out opposite quarters as before. 
This process will be continued as rapidly as possible until the final 
sample is reduced to such amount that all of the final sample thus 
obtained will be contained in the shipping can or jar and sealed air- 
tight. 

The sample will then be forwarded to 

If desired by the coal contractor, permission will be given to him, 
or his representative, to be present and witness the quartering and 
preparation of the final sample to be forwarded to the Government 
laboratories. 

Immediately on receipt of the sample, it will be analyzed and tested 
by the Government, following the method adopted by the American 
Chemical Society, and using a bomb calorimeter. A copy of the result 
will be mailed to the contractor upon the completion thereof. 



136 APPENDIX. 



CAUSES FOR REJECTION. 

A contract entered into under the terms of this specification shall 
not be binding if, as the result of a practical service test of reasonable 
duration, the coal fails to give satisfactory results owing to excessive 
clinkering or to a prohibitive amount of smoke. 

It is understood that the coal delivered during the year will be of 
the same character as that specified by the contractor. It should, 
therefore, be supplied, as nearly as possible, from the same mine or 
group of mines. 

Coal containing percentages of volatile matter, sulphur, and dust 
higher than the limits indicated on page 2 and coal containing a per- 
centage of ash in excess of the maximum limits indicated in the follow- 
ing table will be subject to rejection. 

In the case of coal which has been delivered and used for trial, or 
which has been consumed or remains on the premises at the time of 
the determination of its quality, payment will be made therefor at a 
reduced price, computed under the terms of this specification. 

Occasional deliveries containing ash up to the precentage indicated 
in the column of "Maximum limits for ash," on page 4, may be 
accepted. Frequent or continued failure to maintain the standard 
established by the contractor, however, will be considered sufficient 
cause for cancellation of the contract. 

PRICE AND PAYMENT.* 

Payment will be made on the basis of the price named in the pro- 
posal for the coal specified therein, corrected for variations in heating 
value and ash, as shown by analysis, above and below the standard 
established by contractor in this proposal. For example, if the coal 
contains 2 per cent, more or less, British thermal units than the estab- 
lished standard, the price will be increased or decreased 2 per cent 
accordingly. 

The price will also be further 'corrected for the percentages of ash. 
For all coal which by analysis contains less ash than that established 

* The economic value of a fuel is affected by the actual amount of com- 
bustible matter it contains, as determined by its heating value shown in British 
thermal units per pound of fuel, and also by other factors, among which is its 
ash content. The ash content not only lowers the heating value and decreases 
the capacity of the furnace, but also materially increases the cost of handling 
the coal, the labor of firing, and the cost of removal of ashes, etc. 



COAL AND FUEL OIL SPECIFICATIONS. 



137 



in this proposal a premium of 1 per cent per ton for each whole per 
cent less ash will be paid. An increase in the ash content of 2 per cent 
over the standard established by contractor will be tolerated without 
exacting a penalty for the excess of ash. When such excess exceeds 
2 per cent above the standard established, deductions will be made 
from the price paid per ton in accordance with following table: 





No Deduction 
for Limits 
Below. 


Cents per Ton to be Deducted. 


1 


Establish- 
ed in Pro- 
posal (Per 


2 


4 


7 


12 


18 


25 


35 


5° 


Cent). 


Percentages of Ash in Dry Coal. 


X CO 


5 


7 


7-8 


8-9 


9-IO 


io-ii 


11-12 


12-13 


13-14 


12 


6 


8 


8-9 


9-10 


10-11 


11-12 


12-13 


13-14 


14-15 


13 


7 


9 
10 


9-10 
io-ii 


10-11 
11-12 


11-12 ' 12-13 


i3- J 4 


14-15 
15-16 


15-16 
16-17 


14 


8 


12-13 


13-14 


14-15 


14 


9 


11 


11-12 


12-13 


13-14 


14-15 


15-16 


16-17 


17-18 


15 


10 


12 
13 


12-13 
13-14 


13-14 
14-15 


14-15 

15-16 


15-16 


16-17 

17-18 


17-18 
18-19 




l6 


11 


16-17 


l6 


12 


14 


14-15 


15-16 


l6-I7 


17-18 


18-19 


19-20 




17 


13 


15 


15-16 


16-17 


17-18 


18-I9 


19-20 


20-21 




18 


14 


16 

17 
t8 


16-17 
I7-l8 
18-I9 
I9-2O 
20-2I 


17-18 
18-19 
19-20 
20-21 


18-I9 


I9-2O 
20—2I 


20-21 
21—22 


21-22 




19 


15 
16 


I9-2O 
20-2I 


19 

20 


21-22 


22-23 






17 


19 
20 


21-22 


2 2-23 






21 


18 


21-22 


22-23 








22 















Proposals to receive consideration must be submitted upon this 
form and contain all of the information requested. 

•• 1 190- ■ 

The undersigned hereby agree to furnish to the IT. S 

building at , the coal described, in tons of 2,240 lbs. 

each and in quantity 10 per cent more or less than that stated on 
page 1, as may be required during the fiscal year ending June 30, 
190. ., in strict accordance with this specification; the coal to be de- 
livered in such quantities and at such times as the Government may 
direct. 



138 



APPENDIX. 





Item No. . . 


Item No. . . 


Item No. . . 


Description. 
Commercial name 








Name of mine 








Location of mine 








Name of coal bed 








Size of coal (if coal is 
screened): 
Coal to pass through 
openings 




. . inches -\ round 
f square 
. . inches J bar 


. . inches ^ round 
} square 
. .inches J bar 


Coal to pass over open- 
ings 


\ square 
. inches J bar 


Data to establish a basis for 
payment. 

Per cent of ash in dry coal 
(method of American 
Chemical Society) 




British thermal units in 
coal as delivered 








Price per ton (2,240 lbs.) . . 

















It is important that the above information does not establish a higher 
standard than can be actually maintained under the terms of the contract; 
and in this connection it should be noted that the small samples taken from 
the mine are invariably of higher quality than the coal actually delivered 
therefrom. It is evident, therefore, that it will be to the best interests of the 
contractor to furnish a correct description with average values of the coal 
offered, as a failure to maintain the standard established by contractor will 
result in deductions from the contract price, and may cause a cancellation of 
the contract, while deliveries of a coal of higher grade than quoted will be 
paid for at an increased price. 

Signature 

Address 

Name of corporation 

Name of president 

Name of secretary 

Under what law (State) corporation is organized 



As will be seen from the foregoing specification, the bidder is not 
required to submit a sample of his coal, but is expected to name a 
standard of British thermal units in the coal as it is to be delivered. 
This value is made the basis for purchase, because a correction is thus 
made for the amount of moisture in the coal. It should be noted that 
this value will in all cases be lower than the British thermal units in 
the dry coal, which is usually given in connection with the coal analysis. 
The percentage of ash is also specified, as it is a factor in the successful 
burning of the coal on the grate and as it involves an expense for 
removal from the premises. 



COAL AND FUEL OIL SPECIFICATIONS. 



139 






The following are the essential features of the contracts on which 
a Chicago company is said to purchase and inspect nearly 1,000,000 
tons of coal for its clients in Chicago, Indianapolis, Minneapolis, 
St. Louis, and other cities: 

I. The company agrees to furnish and deliver to the consumer 

at such times and in such quantities as ordered by the 

consumer for consumption at said premises during the term hereof, 
at the consumer's option, either or all of the kinds of coal described 
below; said coals to average the following assays: 



Kind of coal . 



Of size passing through screen having circu- 
lar perforations in diameter 

Of size passing over a screen having circular 
perforations in diameter 

Per cent of moisture in coal as delivered . . 

Per cent of ash in coal as delivered 

British thermal units per pound of dry coal. 

From following county 

From following State 



. inches 
. inches 



. inches 
. inches 



. inches 
. inches 






Coal of the above respective descriptions and specified assays (not 
average assays) to be hereinafter known as the contract grade of the 
respective kinds. 

II. The consumer agrees to purchase from the company all the coal 
required for consumption at said premises during the term of said 
contract, except as set forth in Paragraph III below, and to pay the 
company for each ton of 2000 lbs. avoirdupois of coal delivered and 
accepted in accordance with all the terms of this contract at the follow- 
ing contract rate per ton for coal of each respective contract grade, 
at which rates the company will deliver the following respective numbers 
of British thermal units for 1 cent, the contract guaranty: 



Kind of Coal. 


Contract 

Rate per 

Ton. 


Contract Guaranty. 




$ 

$ 

$ 


equal to net B.T.U. for 1 cent 




equal to net B.T.U. for 1 cent 




equal to net B.T.U. for 1 cent 







Said net British thermal units for 1 cent being in each case deter- 
mined as follows: Multiply the number of British thermal units per 
pound of dry coal by the per cent of moisture (expressed in decimals), 



1 4 o APPENDIX. 

subtract the product so found from the number of British thermal units 
per pound of dry coal, multiply the remainder by 2000, and divide 
this product by the contract rate per ton (expressed in cents) plus 
one-half of the ash percentage (expressed as cents). 

III. It is provided that the consumer may purchase for consumption 
at said premises coal other than herein contracted for, for test purposes, 
it being understood that the total of such coal so purchased shall not 
exceed 5 per cent of the total consumption dur g the term of this 
contract. 

IV. It is understood that the company may deliver coal hereunder 
containing as high as 3 per cent more ash and as high as 3 per cent 
more moisture and as low as 500 fewer British thermal units per pound 
dry than specified above for contract grades. 

V. Should any coal delivered hereunder contain more than the 
per cent of ash or moisture or fewer than the number of British thermal 
units per pound dry allowed under Paragraph IV hereof, the con- 
sumer may, at its option, either accept or reject same. 

VI. All coal accepted hereunder shall be paid for monthly at a price 
per ton determined by taking the average of the delivered values 
obtained from the analyses of all the samples taken during that month, 
said delivered value in each case being obtained as follows: Multiply 
the number of British thermal units delivered per pound of dry coal 
by the per cent of moisture delivered (expressed in decimals), subtract 
the product so found from the number of British thermal units delivered 
per pound of dry coal, multiply the remainder by 2000, divide this 
product by the contract guaranty, and from this quotient (expressed 
as dollars and cents) subtract one-half of the ash percentage delivered 
(expressed as cents). 

The following are the essential features of the specifications used 
by the Interborough Rapid Transit Company of New York in pur- 
chasing about 30,000 tons of coal each month for use in its plants, 
which are among the largest in the United States: 

Preliminary Specifications for Bituminous Coal for the Inter- 
borough Rapid Transit Company. 

Coal must be a good steam, caking, run-of-mine, bituminous coal free 
from all dirt and excessive dust, a dry sample of which will approximate 
the company's standard in heat value and analysis as follows: Carbon, 
71; volatile matter, 20;" ash, 9; B.T.U., 14,100; sulphur, 1.50. 



COAL AND FUEL OIL SPECIFICATIONS. 141 

A small quantity of coal will be taken from each weighing hopper 
just before the hopper is dumped while the lighter is being unloaded. 
These quantities will be thrown into a receptacle provided for the 
purpose, and when the lighter is empty the contents of the receptacle 
will be thoroughly mixed, and a sample of this mixture will be taken 
for chemical analysis. This average sample of coal will be labeled and 
held for one week after the unloading of the lighter. The sample taken 
from the mixture L.r. test will be analyzed as soon as possible after 
being taken. No other sample will be recognized. 

Tests of sample taken from average sample will be made by the 
company's chemist under the supervision of the superintendent. 
Should the contractor question the results of the company's test (a 
copy of which will be mailed to him), the company will, if requested 
by the contractor within three days after copy of test has been mailed 
to him, forward sufficient quantity of the average sample taken from 
each weighing hopper to any laboratory in the city of New York which 
may be agreed upon by the superintendent and the contractor, and 
have said sample analyzed by it, and the results obtained from this 
second test will be considered as final and conclusive. In case the 
disputed values, as obtained in the company's test, shall be found by 
the second test to be 2 per cent or less in error, then the cost of said 
second test shall be borne by the contractor; but if the disputed 
values shall be fo'und to be more than 2 per cent in error, then the cost 
of said second test shall be borne by the company. 

Should there be no question raised by the contractor within the 
three days specified, as to the values of the first analysis, the average 
sample of coal will be destroyed at the end of seven days from date of 
discharge of coal from lighter. Should a second test be made of coal 
taken from any lighter as herein provided, then any penalties to be 
made as set forth in paragraph under " Penalties" will be based on 
the results as obtained from the second test. 

The price to be paid by the company per ton per lighter of coal will 
be based on a table of heat values for excess or deficiency of its standard, 
but subject to deductions as given in the section under " Penalized 
coal," including excess of ash, volatile matter, sulphur, or dust, or less 
than the minimum amount required to be contained in any lighter, 
for coal which shows results less than the company's standard. 

Premiums or deductions are based on a rate of 1 cent per ton for a 
variation of 50 B.T.U. per pound of coal, as indicated in a table a 
few items of which are given below: 



I 4 2 APPENDIX. 

Table for B.T.U. Values. 

For coal in any lighter which is found by test to contain, per pound 
of dry coal, from 

15,501 and above 28 cents per ton above standard 

15,101 to 15,150, both inclusive 20 cents per ton above standard 

14,601 to 14,650, both inclusive 10 cents per ton above standard 

14,101 to 14,150, both inclusive Standard 

13,601 to 13,650, both inclusive 10 cents per ton below standard 

13,101 to 13,150, both inclusive 20 cents per ton below standard 

12,101 to 12,150, both inclusive 40 cents per ton below standard 

No lighter of coal will be accepted which, by trial, in the judgment 
of the superintendent, contains an excessive amount of dry coal dust. 
The decision of the superintendent will be final in this respect. Coal 
taken from such lighter for trial will be subject to the special deduction 
set forth under " Penalized coal," but paid for in all other respects as 
herein provided. 

Coal which is shown by analysis to contain less than 20 per cent of 
volatile matter, 9 per cent of ash, or 1.50 per cent of sulphur, will be 
accepted, without a deduction from the bidder's price, plus or minus 
an amount for excess or deficiency of British thermal unit value, as 
herein provided. Where the analysis gives amounts for any or all 
elements in excess of these quantites, deductions will be made from 
the bidder's price in accordance with the tables of values of volatile 
matter, ash, and sulphur below given, plus or minus the amount for 
excess or deficiency of the standard British thermal unit value, in 
addition to any other deductions which may be made as herein pro- 
vided. 

Table of Deductions for Volatile Matter. 

For coal in any lighter which is found by test to contain, per pound of 

dry coal 

Over 20 per cent and less than 21 per cent 2 cents per ton 

********* 

Over 22.5 per cent and less than 23 per cent. ... 12 cents per ton 
********* 

24 per cent and over 18 cents per ton 

This table is made for the difference of each one-half of 1 per cent 
and the deductions are at the rate of 4 cents for each 1 per cent of 
volatile matter. 



COAL AND FUEL OIL SPECIFICATIONS. 143 

Table of Deductions for Ash. 

For coal in anylighter which is found by test to contain, per pound of 

dry coal 

Over 9 per cent and less than 9.5 per cent 2 cents per ton 

********* 

Over 1 1. 5 per cent and less than 12 12 cents per ton 

********* 

13.5 per cent and over 23 cents per ton 

This table is made for each difference of one-half of 1 per cent and 
at the rate of 4 cents for each 1 per cent increase in the ash. 



Table of Deductions for Sulphur. 

For coal in any lighter which is found by test to contain, per pound of 

dry coal 

Over 1.50 per cent and less than 1.75 per cent . . 6 cents per ton 
********* 

Over 2 per cent and less than 2.25 per cent 10 cents per ton 

********* 

2.50 and over 20 cents per ton 

This table is made out for each difference of one-fourth of 1 per cent 
and at a diminishing rate. 

Should any lighter of coal delivered at the company's docks contain 
less than 700 tons, a deduction of 7 cents per ton will be made from 
the price as determined by the British thermal unit value and analysis, 
in addition to any other penalty provided for herein. Should any 
lighter of coal delivered at the company's docks be rejected by the super- 
intendent on account of excessive amount of coal dust, then a reduction 
of 25 cents per ton will be made from the price as determined by the 
British thermal unit value and analysis, for the coal taken from said 
lighter, in addition to any other penalty which may be made as herein 
provided. Should any lighter of coal be delivered in other than self- 
trimming lighters as herein provided, a deduction of 7 cents per ton 
will be made from the price as determined by the British thermal unit 
value and analysis, exclusive of any other penalty which may be made 
as herein provided. 

The contractor's bill of lading will be checked by the company's 
scales. Should there be a deficiency of 1 per cent or more between 



144 



APPENDIX. 



the bill of lading and the company's weights, then the company's 
weights will be taken as correct. 

When the contractor has been notified by the company to deliver 
coal under this contract; a further notice may be given requiring the 
contractor to make delivery of the coal so ordered within twelve hours 
after the receipt of said second notice. Should the contractor, for any 
reason, fail to deliver the coal so ordered within twelve hours after 
the receipt of said second notice and in accordance with the require- 
ments therein as to place of delivery, the company shall be at liberty 
to buy coal in the open market, and the contractor will make good 
to the company any difference there may be between the price paid 
by the company for said coal in open market and the price the com- 
pany would have paid to the contractor had the coal been delivered 
by it in accordance with the requirements of said notices from the 
company, or said difference may be deducted from any money then 
due or thereafter to become due to the contractor under the contract 
to be entered into. 



FUEL OIL SPECIFICATIONS. 

The Specifications of the U. S. Government are as follows*: 

GENERAL SPECIFICATIONS. 

(i) In determining the award of a contract, consideration will be 
given to the quality of the fuel offered by the bidders, as well as the 
price, and should it appear to be to the best interest of the Govern- 
ment to award a contract at a higher price than that named in the 
lowest bid or bids received, the contract will be so awarded. 

(2) Fuel oil should be either a natural homogeneous oil or a homo- 
geneous residue from a natural oil ; if the latter, all constituents having 
a low flash-point should have been removed by distillation; it should 
not be composed of a light oil and a heavy residue mixed in such pro- 
portions as to give the density desired. 

(3) It should not have been distilled at a temperature high enough 
to burn it, nor at a temperature so high that flecks of carbonaceous 
matter began to separate. 

* J. C. Allen, J. Ind. and Eng. Chem., 3, 730 (1911). 



COAL AND FUEL OIL SPECIFICATIONS. 145 

(4) It should not flash below 60 ° C. (140 F.) in a closed Abel- 
Pensky or Pensky-Martens tester. 

(5) Its specific gravity should range from 0.85 to 0.96 at 15 C. 
(59° F-)i the oil should be rejected if its specific gravity is above 0.97 
at that temperature. 

(6) It should be mobile, free from solid or semi-solid bodies, and 
should flow readily, at ordinary atmospheric temperatures and under 
a head of 1 foot of oil, through a 4-inch pipe 10 feet in length. 

(7) It should not congeal nor become too sluggish to flow at o° C. 
(32° F.). 

(8) It should have a calorific value of not less than 10,000 calories 
per gram * (18,000 B.T.U. per pound), 10,250 calories to be the standard. 
A bonus is to be paid or a penalty deducted according to the method 
stated under Section 21, as the fuel oil delivered is above or below 
this standard, f 

(9) It should be rejected if it contains more than 2 per cent water. 

(10) It should be rejected if it contains more than 1 per cent sulphur. 

(11) It should not contain more than a trace of sand, clay, or dirt. 

(12) Each bidder must submit an accurate statement regarding 
the fuel oil he proposes to furnish. This statement should show: 

(a) The commercial name of the oil. 

(b) The name or designation of the field from which the oil is obtained. 

(c) Whether the oil is a crude oil, a refinery residue, or a distillate. 

(d) The name and location of the refinery ,*if the oil has been refined 
at all. 

(13) The fuel oil is to be delivered f.o.b. cars or vessel, according 
to the manner of shipment, at such places, at such times, and in such 
quantities as may be required, during the fiscal year ending 

(14) Should the contractor, for any reason, fail to comply with a 
written order to make delivery, the Government is to be at liberty to 
buy oil in the open market, and charge against the contractor any excess 
of price, above the contract price, of the fuel oil so purchased. 

* Calories X 1.8 = B.T.U. per pound. 

t It is important that the standard fixed should not be higher than can be 
maintained under the terms of the contract. In the absence of information 
as to the heating value of the oil, the Bureau of Mines will analyze samples 
taken from the deliveries to establish the standard heating value, expressed 
in calories or B.T.U. It will be to the best interests of the contractor to specify 
a fair standard for the fuel oil he offers, since failure to maintain that standard 
will cause deduction from the contract price and possibly the cancellation 
of the contract, while deliveries of higher quality than the standard will result 
in the contractor receiving premiums. 



Z46 APPENDIX. 



Sampling. 

(15) Deliveries of fuel oil will be sampled by a representative of the 
Government. Whenever such action is practicable, the oil will be 
sampled as it is being delivered. The final sample will be made from 
samples taken from as large a proportion of the delivery as practicable, 
in order that the final sample may truly represent the delivery. 

(16) The final sample will be sealed and forwarded to the Federal 
Bureau of Mines, Pittsburgh, Pa., for analysis. 

(17) If the contractor so desires, permission will be given him, or 
his representative, to witness the sampling of the delivery and the 
preparation of the final sample. 

(18) The final sample will be analyzed and tested immediately afte r 
its receipt in Pittsburgh. 

Causes for Rejection. 

(19) A contract entered into~under the terms of these specifications 
shall not be binding if, as the result of a practical service test of reason- 
able duration, the fuel oil fails to give satisfactory results. 

(20) It is understood that the fuel oil delivered during the terms of 
the contract shall be of the quality specified. The frequent or con- 
tinued failure of the contractor to deliver oil of the specified quality 
will be considered sufficient cause for the cancellation of the contract. 

Price and Payment. 

(21) Payment for deliveries will be made on the basis of the price 
named in the proposal for the fuel oil corrected for variations in heat- 
ing value,* as shown by analysis, above cr below the standard fixed 
by the contractor. This correction is a pro rata one and the price is 
to be determined by the following formulae: 

Delivered calories per gram (or B.T.U. per lb.)Xcontract price 
Standard calories per gram (or B.T.U. per lb.) 

= price to be paid. 

* The value of an oil as fuel is in proportion to the total combustible matter 
it contains as shown by its heating value. This value may be expressed in 
small calories per gram of B.T.U. per pound. Sulphur, moisture, and earthy 
matter lower the heating value of an oil and decrease the furnace capacity; 
they also may have a deleterious effect on boiler and furnace, and may impair 
the operation of burners. 



COAL AND FUEL OIL SPECIFICATIONS. 147 

Water that accumulates in the receiving tank will be drawn off and 
measured periodically. Proper deduction will be made by subtracting 
the weight of the water from the weight of the oil deliveries. 

Determination of Weight from Volume. 

The specifications given on the preceding pages provide for the 
purchase of fuel oil by weight. As such oil is frequently delivered by 
volume, it is important to note the temperature of a delivery and to 
allow for the expansion due to this temperature when computing the 
weight of the delivery from the volume. From the volume of the oil 
at the temperature of delivery, the volume at standard temperature 
(15 C.) should be computed in the manner given below. 

The coefficient of expansion of ordinary fuel oil residues of asphaltic 
base is approximately 0.0006 per i°C. 

Hence if the temperature (1V C.) of the delivery is above 15 C, 
then (N° C-15 C.) X 0.0006 = correction. 

This correction is to be added to the specific gravity at N° C. to 
give the standard specific gravity, that at 15 C. 

If the temperature (N° C.) of the oil delivered is below 15 C, the 
correction ((15 C— A T0 C.)Xo.ooo6) is to be subtracted from the 
specific gravity at 15 C. 

Since a gallon of water at a temperature of 15 C. weighs 8.3316 lbs., 
the weight in pounds of a gallon of oil at 15 C. is 8.3316 times the specific 
gravity of the oil at that temperature. 

Similarly, since a cubic foot of water at 15 C. weighs 62.3425 lbs., 
the weight in pounds of a cubic foot of oil at 15 C. is 62.3425 times its 
specific gravity at that temperature. 

Reporting Analyses of Fuel Oil. 

The following form is used by the Bureau of Mines in reporting the 
results of an analysis of a sample of fuel oil: 

DEPARTMENT OF THE INTERIOR. 

BUREAU of mines. 

Washington, D. C, 191 — . 

Sir: 

In reference to the sample of fuel petroleum represent- 

(Quantity.) 

ing of petroleum delivered at a temperature of .... ° C. by 

(Quantity.) 
the as a product, from the 

(Company delivering.) (Crude, residue, or distillate.) (Lease.) 



i 4 8 APPENDIX. 



. , , to the . . , 

(Field or district.) (County.) (State.) (Department receiving.) 

at on ,1 have the honor to report as 

(City.) (Date of delivery.) 

follows : 



Specific gravity at 15 C 

(Baume at 50° F.) 

Calorie per gram 

(B.T.U. per pound) 

Water, per cent 

Sulphur, per cent . 

Earthy matter, sand, etc., per cent 

Flash-point, ° C. (Abel-Pensky, or Pensky-Mar- 

tens, closed tester) 

Burning point, ° C. (same tester, opened) 

Remarks : 



The above information is for the use of the Government and the dealer or 
operator furnishing the oil. It is to be considered confidential until it is pub- 
lished by the United States Government. 

Respectfully, 

Chief Clerk, 
Certified : 

Petroleum Chemist. 
SAMPLING PETROLEUM OR FUEL OIL. 

GENERAL STATEMENT. 

The accuracy of the sampling and, in turn, the value of the analysis 
must necessarily depend on the integrity, alertness, and ability of the 
person who does the sampling. No matter how honest the sampler 
may be, if he lacks alertness and sampling ability, he may easily make 
errors that will vitiate all subsequent work and render the results of 
tests and analyses utterly misleading. A sampler must be always on 
the alert for sand, water, and foreign matter. He should note any 
circumstances that appear suspicious, and should submit a critical 
report on them, together with samples of the questioned oil. 



COAL AND FUEL OIL SPECIFICATIONS. 149 

SAMPLING WAGON DELIVERIES. 

SAMPLING WITH A DIPPER. 

Immediately after the oil begins to flow from the wagon to the 
receiving tank, a small dipper holding any definite quantity, say, 0.5 
liter (about 1 pint), is filled from the stream of oil. Similar samples 
are taken at equal intervals of time from the beginning to the end of 
the flow — a dozen or more dipperfuls in all. These samples are poured 
into a clean drum and well shaken. If the oil is heavy, the dipperfuls 
of oil may be poured into a clean pail and thoroughly stirred. For a 
complete analysis the final sample should contain at least 4 liters (about 
1 gallon). This sample should be poured into a clean can, soldered 
tight and forwarded to the laboratory. 

It is important that the dipper be filled with oil at uniform intervals 
of time and that the dipper be always filled to the same level. The 
total quantity of oil taken should represent a definite quantity of oil 
delivered and the relation of the sample to the delivery should be 
always be stated, for instance: "1 gallon sample representing 1 wagon- 
load of 20 barrels." 

CONTINUOUS SAMPLING. 

Instead of taking samples with a dipper, it may be more convenient 
to take a continuous sample. This may be taken by allowing the 
oil to flow at a constant and uninterrupted rate from a J-inch cock on 
the under side of the delivery pipe during the entire time of discharge. 
The continuous sample should be thoroughly mixed in a clean drum 
or pail, and at least 4 liters (about 1 gallon) of it forwarded for analysis. 
A careful examination should be made for water, and if the first dipperful 
shows water this dipperful should be thrown into the receiving tank 
and not mixed with the sample for analysis. 

MIXED SAMPLES. 

If the oil delivered during any definite period of time, say one month, 
be from the same source and of uniform quality (but only in case it is 
of uniform quality), it may suffice to pour definite proportional quanti- 
ties of the dipper and the continuous samples taken during this period 
into a tinned can or drum having a tight screw cap or bung. An iron 
drum should not be used, since even a clean iron surface will absorb 
sulphur by long contact with a sulphur-containing oil, and this sulphur 
will be lost to the analyst. At the end of the month a number of round, 



l 5 o APPENDIX. 

clean stones should be put into the drum and the drum should be rolled 
to insure intimate mixing. Then 4 liters (about 1 gallon) of the gross 
sample should be taken for analysis. The drum should be drained, 
rinsed clean with gasoline, dried, and made ready for a second sampling. 
The all-important point is that the gross sample, whatever the 
manner of sampling, shall be made up of equivalent portions of oil 
taken at regular intervals of time, so that the sample finally forwarded 
for analysis will truly represent the entire shipment. 

SAMPLING A LARGE TANK OR RESERVOIR. 

Water or earthy matter settles on standing. Hence, before a large 
stationary tank or reservoir is sampled the character of the contents 
at the bottom should be ascertained by dredging with a long-handled 
dipper, and the content of the dipper should be examined critically. 
If a considerable quantity of sediment is brought up, it should be cause 
for rejecting the oil. 

The sampling of a large stationary tank or reservoir of oil, par- 
ticularly if the oil has stood so long that it has begun to stratify, or 
form layers of different density, may be done as follows: 

The sampler should procure an ordinary iron pipe, or preferably a 
tinned tube, 1 inch in diameter and long enough to reach from above 
the manhole, where he can grasp it, to the bottom of the tank. The 
lower end of the pipe should be reamed out with a round file. A conical 
plug of cork, wood, or other suitable material should be fitted to this 
end, and a strong, stiff wire, such as the ordinary telegraph wire, run 
through this plug and up through the pipe to a point where it can be 
grasped firmly by the sampler. A pull on the wire will close the 
bottom of the pipe, and a rap against the bottom of the tank will drive 
the plug home and make an oil-tight seal or valve. 

To operate this sampling device, the sampler should remove the 
plug, allow it to drop some three inches below the bottom of the pipe, 
and let it hang there by the wire extending above the pipe. Then 
holding the pipe, open at top and bottom, in a vertical position, the 
sampler should allow it to sink slowly through the oil to the bottom 
of the tank. He should do this slowly and with care, so that the pipe 
will penetrate the oil without agitating it and will thus cut a repre- 
sentative core of oil from the surface to the bottom. When the pipe 
touches the bottom, the sampler should draw up the slack of the wire 
and pull the plug into place; then he should strike the plug smartly 
against the bottom of the tank, thereby driving it home and sealing 



COAL AND FUEL OIL SPECIFICATION'S. 151 

the pipe. He can then withdraw the pipe and pour the oil into the 
sampling can. If it seems desirable,^he should "core " or "sample" 
a reservoir at regularly spaced points, unite these samples, mix them 
thoroughly, and take 4 liters (about 1 gallon) of the gross sample for 
analysis. 

Instead of a pipe sampler, a bottle holding half a liter (about 1 pint) 
may be used. It should be securely fastened to a long pole and have 
a loosely-fitted stopper tied to a strong cord. The bottle, corked and 
empty, isimmersed to any desired point within the mass of oil, and the 
stopper is pulled out. The bottleful of oil is poured into a suitable 
receiving vessel, and the bottle thoroughly drained is made ready for 
a second filling. Bottlefuls of oil taken in this way from points sym- 
metrically placed throughout the mass of oil, will, if properly mixed, 
provide an excellent gross sample from which to take the 4-liter (1 gallon) 
sample for analysis. 

SAMPLING A SINGLE DRUM. 

A single drum may be sampled with a glass tube. This tube, open 
at both ends, should be grasped at the top, held vertically, inserted in 
the drum without agitating the oil, and allowed to cut its way slowly 
to the bottom of the drum. The upper end should then be closed with 
the thumb or forefinger of the hand holding it, the tube withdrawn, 
and the oil on the outside wiped off with the fingers of the other hand. 
The sample in the tube can then be transferred to a small can, and. 
forwarded for analysis. 

FORWARDING SAMPLES. 

The sample should be forwarded in a glass bottle or carboy or in a 
tin can, preferably in the latter, because less liable to breakage. If a 
tin can is used the cap should be soldered tight. The can should not 
be filled completely; about an eighth of an inch of space should be 
left to allow for possible expansion of the oil. 

The can should be sealed as soon as it is filled to avoid loss by vola- 
tilization of the lighter constituents of the sample. x\fter the can has 
been filled and tightly soldered, it should be wiped clean and carefully 
examined for pinholes or small leaks. All leaks should be soldered 
before the can is packed for shipment. 

The bottle or can should be carefully labeled. The following form 
of label,* used by the Bureau of Mines, should be placed on samples 
shipped to the bureau: 

* These labels will be furnished on request. 



I S 2 APPENDIX. 

DEPARTMENT OF THE INTERIOR. 

BUREAU OF MINES. 

Information to Accompany Each Sample of Fuel Petroleum Submitted 

for Analysis. 



Sample number Sampled by 

Oil delivered to 

(Department receiving.) 
Place of delivery 

(City.) (State.) 

Quantity of oil delivered 

Date of delivery 

Temperature of oil as delivered .... ° C 

Name of contractor 

Nature of oil 

(Crude, residue, or distillate.) 
If refined to any degree, state name and location of refinery. 



Source of oil 

(Lease.) (Field or district.) (County.) (State.) 

Remarks 



Date of forwarding sample. 

Forwarded by via . 



(Express or fast freight.) (Transportation line.) 

Date of receipt of sample by Bureau of Mines 

Condition of sample when received by Bureau of Mines 



The label should be carefully written with a hard lead pencil on a 
strong mailing tag, and this tag should be securely tied to the can. 
The lead pencil should be pressed firmly against the tag so as to indent 
its surface. An inscription thus written is legible even after the paper 
has been wet with oil. Gummed labels should not be used; they are 
easily detached if slightly moistened, and may be lost. A duplicate 
copy of the record on the label should be mailed to the engineer in charge, 
Bureau of Mines, Pittsburgh, Pa. 



COAL AXD FUEL OIL SPECIFICATIONS. 153 



SAMPLING GAS FROM A WELL. 

Since the gas associated with oil is an ideal fuel and illuminant, and 
the literature dealing with the composition of natural gas is scanty, 
a description of the method of sampling such gas for analysis is here 
given. 

For taking a sample of gas under pressure from an oil well a cloth 
funnel should be made by folding and sewing any strong, closely- woven 
cloth into the form of a cornucopia. The larger end of this funnel 
should be large enough to encompass the gas pipe from which the 
sample is to be taken. The smaller end, or apex, of the funnel should 
should be securely tied about one end of a flexible rubber tube i or 2 feet 
long and one-fourth to one-half inch in diameter. If there is a gas jet 
at the well, one end of the rubber tube may be attached directly to the 
jet. 

A gas-sampling bottle should be procured, if practicable, from the 
Bureau of Alines, Pittsburgh, Pa. If such a bottle is not at hand, a 
1- or 2-liter (1- or 2-quart) bottle with a well-ground, tight-fitting glass 
stopper may be used. The bottle should be thoroughly cleansed and 
dried. A large perfume bottle or an acid bottle, such as may be obtained 
from a drug store, will usually answer. A glass stopper is essential, 
for a cork or rubber stopper may leak even though it appears to be 
hermetically sealed with wax; moreover, a cork or rubber stopper 
may contaminate the gas. 

To collect a sample, the funnel should be tied firmly about the end 
of the gas pipe. The funnel and the rubber tube should then be thor- 
oughly flushed with the gas to rid them of air. The free end of the tube 
should go to the bottom of the sample bottle. The bottle should be 
fastened bottom up and the gas allowed to blow strongly into it for at 
least a quarter of an hour to insure complete expulsion of air. If the 
gas pressure is low, the gas should be allowed to blow longer, or until 
it is certain that all air has been expelled from the bottle. Meanwhile 
the stopper of the bottle should have been well greased with vaseline. 

While the gas is still blowing through the tube the tube should be 
slowly withdrawn. The stopper should be put in just as soon as the 
tube is withdrawn and should be turned firmly into place. Then the 
bottle should be turned up and a spoonful of melted paraffin poured 
over the stopper. The stopper should be secured with elastic band. 

A strong tag should be tied to the bottle by a stout cord. This tag 
should be labeled as follows: 






154 APPENDIX. 

Gas Sample. 



Sampled by. 
Date 



Well Lease 

Number. 

Section Township Range . 

District County State . . 

Remarks 



The bottle should be packed securely in a box and forwarded to the 
Bureau of Mines, Pittsburgh, Pa. A duplicate copy of the label 
should be sent to the same address. 



INDEX. 



FAGB 

Acetylene, calorific power of 129 

Acid, hydrochloric, reagent 63 

Air, permissible excess of 45 

Air-pumps, Bunsen's 8 

, Richards' 8 

, steam 9 

Alcohol, denatured, calorific power of 129 

, ethyl, calorific power of L29 

, methyl, calorific power of 1 29 

Anthracite coal, analysis of ... . 75 

Aqueous vapor, specific heat 37 

, table of 127 

Aspirator 68 

, Muencke's 68 

Benzoic acid, calorific power in 

Benzophenon, boiling-point : 29 

Berthier's method of determining calorific power of coal 113 

Bituminous coal, analysis of 74 

, varieties 73 

Blast-furnace gas, analysis of 80 

Boiling-point of various substances 30 

Brown coal 73 

, analysis of 73 

, calorific power of 130 

Bunte's gas apparatus 19 

method for determining quantity of heat passing up chimney 40 

Calculations 32 

Calorimeters of Barrus 95 

Fischer 95 

Hempel 96 

Emerson 96 

Thompson, L 96 



156 INDEX, 

PAGE 

Calorimeters of Thomson, W 95 

Cane sugar, calorific power in 

Carbon dioxide, correct percentage of 43 

, determination of 15, 20, 23, 52 

, specific heat 37 

Carbonic oxide,, determination of 16, 21, 24, 53 

, loss due to formation of 45 

, specific heat .37 

Charcoal, analysis of 76 

, preparation 75 

Coal, air required for combustion 75 

, calorific power 75 

, formation of 72 

, method of analysis 84 

, specifications 133 

Coal-gas, analysis of 82 

, calorific power 82 

, manufacture of 82 

Coke, analysis of 77 

, calorific power of 130 

, determination of 85 

, preparation 76 

Coke-oven gas, calorific power 82. 

Coke-ovens 76 

Cooling correction in calorimetry 104 

Course in gas analysis. 69 

Cuprous chloride acid, reagent 63 

, ammoniacal reagent 64 

Elliott's gas apparatus 22 

Emerson bomb 96 

Formulae, Bunte's, for calorific power of coal 114 

, Lunge's, for heat passing up chimney 43 

, Marks', for carbon in coal 86 

, Maujer's, for heating value of fixed carbon 115 

, Noyes', for calculation of heat lost 43 

, Ratio of air used to that theoretically necessary 31 

Fuel, determination of calorific power 95 

, loss due to unconsumed 45 

Fuel oil, specifications 144 



INDEX. 157 

PAGE 

Fuels, method of analysis of: ash 92 

carbon 86, 88 

coke and volatile matter 85 

hydrogen 88 

moisture 85 

nitrogen 92 

oxygen 92 

sulphur 92 

Fuming sulphuric acid, reagent 63 

Gas-calorimeter, Junkers' . 116 

composimeter of Uehling 26 

Gas, determination of calorific power by calculation 121 

, ignition temperatures of 128 

laboratory, arrangement of 67 

Gasoline, calorific power of 129 

, vapor determination of 95 

Generator gas, see Producer-gas. 

Hempel's gas apparatus 40, 48, 49 

Hydrccarbons, determination of 16, 25, 53, 54 

Hydrogen,- determination of 52, 58, 59 

, reagent 65 



Ignition temperatures of gases 128 

" Illuminants," calorific power of 129 

determination of 53 

Illuminating-gas, Boston, analysis of 122 

, calorific power (Calculated) 124 

, manufacture 82 

, method of analysis of 52 

Iron tubes, action of uncooled gases upon 3 

wire-, calorific power no 

Junkers' gas calorimeter 116 

Kerosene, calorific power of ........ 129 

Laboratory, arrangement of . . 67 

Lead, quantity reduced, a measure of the calorific power 113 

Lignite... ........ .73 



158 INDEX. 

PAGB 

Melting-point boxes 31 

Melting-point of various substances 131 

Mercury, reagent 65 

Methane, determination of 54 

Moisture in coal, determination of 85 

Naphthalene, boiling-point 29 

, calorific power no 

Natural gas, analysis of 80 

, calorific power 82 

Nitrogen, determination of, in coal 92 

, in gases 16, 60 

, specific heat 37 

Oil fuel 79, 1 29, 144 

Orsat's gas apparatus 12 

Otto-Hoffman coke-ovens 76 

Oxygen, determination of, in air 51,52 

, in coal 92 

, in gases 16, 21, 24, 51, 53 

, permissible percentage of 45 

, specific heat 37 

Palladous chloride, reagent 66 

Peat, analysis of 71 

briquettes 71 

, calorific power 71 

, formation 71 

, moisture in 71 

Petroleum, crude, analysis of 80 

, calorific power 80, 1 29 

, formation of 79 

Phosphorus, reagent 66 

Potassium hydrate, reagent 66 

pyrogallate, reagent 66 

" Pounds of air per pound of coal " 32, 35, 39 

Producer-gas, analysis of 81 

, calorific power 81 

Pyrometer, Le Chatelier's thermoelectric 29 

Quantity of heat passing up chimney 33j36, 39 



INDEX. 159 

PAGE 

Ratio of air used to that theoretically necessary 34, 39 



Sampling apparatus. 3, 6 

gases, method of 2 

, tubes for 3 

solid fuels, method of 84 

Semet-Solvay coke-ovens 76 

Semi-bituminous coal, analysis of 74 

Sodium hydrate, reagent 67 

pyrogallate, reagent 67 

Specific heat of various gases 37 

oils 128 

Specifications for coal 133 

fuel oil 144 

Spontaneous combustion of coal 78 

Storage of coal 78 

Sugar, calorific power in 

Sulphur, boiling-point . . 29 

Sulphuric acid, fuming, reagent 63 

Table of calorific power of gases 129 

liquids 129 

solids 130 

melting-points of metals and salts 131 

metric and English systems 132 

quantity of air necessary to burn gases 128 

solubility of gases 131 

specific gravity of gases 130 

heat of gases 37 

various fuel oils 128 

tension of aqueous vapor 127 

theoretical quantity of air supplied 126 

volumetric specific heats of gases 127 

weights of aqueous vapor in air 127 

weights of gases 130 

Tanbark, calorific power of 130 

Temperature, measurement of 28 

Thermometer 28 

, testing of 28 

Tubes for sampling 3 



160 INDEX. 

PAGE 

Volatile matter, determination of 85 

Water-gas, analysis of 81 

, calorific power 81 , 

Wheat straw, calorific power 130 

Wood, analysis of 70 

, calorific power 71 

, moisture in , 70, 7 1 




Wiley Special Subject Catalogues 

For convenience a list of the Wiley Special Subject 
Catalogues, envelope size, has been printed. These 
are arranged in groups — each catalogue having a key 
symbol. (See special Subject List Below). To 
obtain any of these catalogues, send a postal using 
the key symbols of the Catalogues desired. 



1 — Agriculture. Animal Husbandry. Dairying. Industrial 
Canning and Preserving. 

2— Architecture. Building. Masonry. 

3 — Business Administration and Management. Law. 

Industrial Processes: Canning and Preserving; Oil and Gas 
Production; Paint; Printing; Sugar Manufacture; Textile. 

CHEMISTRY 

4a General; Analytical, Qualitative and Quantitative; Inorganic; 
Organic. 

4b Electro- and Physical; Food and Water; Industrial; Medical 
and Pharmaceutical; Sugar. 

CIVIL ENGINEERING 

5a Unclassified and Structural Engineering. 

5b Materials and Mechanics of Construction, including; Cement 

and Concrete; Excavation and Earthwork; Foundations; 

Masonry. 

5c Railroads; Surveying. 

5d Dams; Hydraulic Engineering; Pumping and Hydraulics; Irri- 
gation Engineering; River and Harbor Engineering; Water 
Supply. 

(Over) 






CIVIL ENGINEERING— Continued 
5e Highways; Municipal Engineering; Sanitary Engineering; 
Water Supply. Forestry. Horticulture, Botany and 
Landscape Gardening. 



6 — Design. Decoration. Drawing: General; Descriptive 
Geometry; Kinematics; Mechanical. 

ELECTRICAL ENGINEERING— PHYSICS 

7 — General and Unclassified; Batteries; Central Station Practice; 
Distribution and Transmission; Dynamo-Electro Machinery; 
Electro-Chemistry and Metallurgy; Measuring Instruments 
and Miscellaneous Apparatus. 



8 — Astronomy. Meteorology. Explosives. Marine and 
Naval Engineering. Military. Miscellaneous Books. 

MATHEMATICS 

9 — General; Algebra; Analytic and Plane Geometry; Calculus; 
Trigonometry; Vector Analysis. 

MECHANICAL ENGINEERING 

10a General and Unclassified; Foundry Practice; Shop Practice. 
10b Gas Power and Internal Combustion Engines; Heating and 
Ventilation; Refrigeration. 

10c Machine Design and Mechanism; Power Transmission; Steam 
Power and Power Plants; Thermodynamics and Heat Power. 
11 — Mechanics. 

12 — Medicine. Pharmacy. Medical and Pharmaceutical Chem- 
istry. Sanitary Science and Engineering. Bacteriology and 
Biology. 

MINING ENGINEERING 

13 — General; Assaying; Excavation, Earthwork, Tunneling, Etc.; 
Explosives; Geology; Metallurgy; Mineralogy; Prospecting; 
Ventilation. 



